GuString is now an ordinary C string - it makes live easier. In addition PgfSymbolKS, PgfExprFun and PgfLiteralStr now keep their strings as embedded flexible arrays. The latest change gives us the same compactness as the old representation but it is a lot easier to use.

src/runtime/c/gu/map.c

@@ -4,11 +4,13 @@
 #include <gu/map.h>
 #include <gu/assert.h>
 #include <gu/prime.h>
+#include <gu/string.h>
 
 typedef enum {
 	GU_MAP_GENERIC,
 	GU_MAP_ADDR,
-	GU_MAP_WORD
+	GU_MAP_WORD,
+	GU_MAP_STRING
 } GuMapKind;
 
 typedef struct GuMapData GuMapData;
@@ -66,6 +68,9 @@ gu_map_entry_is_free(GuMap* map, GuMapData* data, size_t idx)
 	} else if (map->kind == GU_MAP_WORD) {
 		GuWord key = ((GuWord*)data->keys)[idx];
 		return key == 0;
+	} else if (map->kind == GU_MAP_STRING) {
+		GuString key = ((GuString*)data->keys)[idx];
+		return key == NULL;
 	}
 	gu_assert(map->kind == GU_MAP_GENERIC);
 	const void* key = &data->keys[idx * map->key_size];
@@ -137,6 +142,27 @@ gu_map_lookup(GuMap* map, const void* key, size_t* idx_out)
 		gu_impossible();
 		break;
 	}
+	case GU_MAP_STRING: {
+		GuHasher* hasher = map->hasher;
+		GuEquality* eq = (GuEquality*) hasher;
+		GuHash hash = hasher->hash(hasher, key);
+		size_t idx = hash % n;
+		size_t offset = (hash % (n - 2)) + 1;
+		while (true) {
+			GuString entry_key =
+				((GuString*)map->data.keys)[idx];
+			if (entry_key == NULL && map->data.zero_idx != idx) {
+				*idx_out = idx;
+				return false;
+			} else if (eq->is_equal(eq, key, entry_key)) {
+				*idx_out = idx;
+				return true;
+			}
+			idx = (idx + offset) % n;
+		}
+		gu_impossible();
+		break;
+	}
 	default:
 		gu_impossible();
 	}
@@ -179,6 +205,11 @@ gu_map_resize(GuMap* map)
 			((const void**)data->keys)[i] = NULL;
 		}
 		break;
+	case GU_MAP_STRING:
+		for (size_t i = 0; i < data->n_entries; i++) {
+			((GuString*)data->keys)[i] = NULL;
+		}
+		break;
 	default:
 		gu_impossible();
 	}
@@ -195,6 +226,8 @@ gu_map_resize(GuMap* map)
 		void* old_key = &old_data.keys[i * key_size];
 		if (map->kind == GU_MAP_ADDR) {
 			old_key = *(void**)old_key;
+		} else if (map->kind == GU_MAP_STRING) {
+			old_key = (void*) *(GuString*)old_key;
 		}
 		void* old_value = &old_data.values[i * value_size];
 
@@ -268,6 +301,8 @@ gu_map_insert(GuMap* map, const void* key)
 		}
 		if (map->kind == GU_MAP_ADDR) {
 			((const void**)map->data.keys)[idx] = key;
+		} else if (map->kind == GU_MAP_STRING) {
+			((GuString*)map->data.keys)[idx] = key;
 		} else {
 			memcpy(&map->data.keys[idx * map->key_size],
 			       key, map->key_size);
@@ -296,6 +331,8 @@ gu_map_iter(GuMap* map, GuMapItor* itor, GuExn* err)
 		void* value = &map->data.values[i * map->value_size];
 		if (map->kind == GU_MAP_ADDR) {
 			key = *(const void* const*) key;
+		} else if (map->kind == GU_MAP_STRING) {
+			key = *(GuString*) key;
 		}
 		itor->fn(itor, key, value, err);
 	}
@@ -323,8 +360,10 @@ gu_map_enum_next(GuEnum* self, void* to, GuPool* pool)
 		en->x.value = &en->ht->data.values[i * en->ht->value_size];
 		if (en->ht->kind == GU_MAP_ADDR) {
 			en->x.key = *(const void* const*) en->x.key;
+		} else if (en->ht->kind == GU_MAP_STRING) {
+			en->x.key = *(GuString*) en->x.key;
 		}
-		
+
 		*((GuMapKeyValue**) to) = &en->x;
 		break;
 	}
@@ -365,10 +404,12 @@ gu_make_map(size_t key_size, GuHasher* hasher,
 	GuMapKind kind =
 		((!hasher || hasher == gu_addr_hasher)
 		 ? GU_MAP_ADDR
+		 : (hasher == gu_string_hasher)
+		 ? GU_MAP_STRING
 		 : (key_size == sizeof(GuWord) && hasher == gu_word_hasher)
 		 ? GU_MAP_WORD
 		 : GU_MAP_GENERIC);
-	if (kind == GU_MAP_ADDR) {
+	if (kind == GU_MAP_ADDR || kind == GU_MAP_STRING) {
 		key_size = sizeof(GuWord);
 	}
 	GuMapData data = {

src/runtime/c/gu/seq.c

@@ -427,13 +427,3 @@ gu_buf_out(GuBuf* buf, GuPool* pool)
 
 GU_DEFINE_KIND(GuSeq, GuOpaque);
 GU_DEFINE_KIND(GuBuf, abstract);
-
-char*
-gu_char_buf_str(GuCharBuf* chars, GuPool* pool)
-{
-	size_t len = gu_buf_length(chars);
-	char* data = gu_buf_data(chars);
-	char* str = gu_new_str(len, pool);
-	memcpy(str, data, len);
-	return str;
-}

src/runtime/c/gu/seq.h

@@ -135,13 +135,6 @@ gu_buf_heapify(GuBuf *buf, GuOrder *order);
 
 GuSeq*
 gu_buf_freeze(GuBuf* buf, GuPool* pool);
-
-typedef GuBuf GuCharBuf;
-typedef GuBuf GuByteBuf;
-
-char*
-gu_char_buf_str(GuCharBuf* chars, GuPool* pool);
-
 #endif // GU_SEQ_H_
 
 #if defined(GU_OUT_H_) && !defined(GU_SEQ_H_OUT_)

src/runtime/c/gu/string.c

@@ -7,21 +7,17 @@
 #include <gu/assert.h>
 #include <stdlib.h>
 
-const GuString gu_empty_string = { 1 };
-
 struct GuStringBuf {
-	GuByteBuf* bbuf;
+	GuBuf* buf;
 	GuOut* out;
 };
 
 GuStringBuf*
 gu_string_buf(GuPool* pool)
 {
-	GuBuf* buf = gu_new_buf(uint8_t, pool);
-	GuOut* out = gu_buf_out(buf, pool);
 	GuStringBuf* sbuf = gu_new(GuStringBuf, pool);
-	sbuf->bbuf = buf;
+	sbuf->buf = gu_new_buf(char, pool);
-	sbuf->out = out;
+	sbuf->out = gu_buf_out(sbuf->buf, pool);
 	return sbuf;
 }
 
@@ -31,176 +27,64 @@ gu_string_buf_out(GuStringBuf* sb)
 	return sb->out;
 }
 
-static GuString
-gu_utf8_string(const uint8_t* buf, size_t sz, GuPool* pool)
-{
-	if (sz < GU_MIN(sizeof(GuWord), 128)) {
-		GuWord w = 0;
-		for (size_t n = 0; n < sz; n++) {
-			w = w << 8 | buf[n];
-		}
-		w = w << 8 | (sz << 1) | 1;
-		return (GuString) { w };
-	}
-	uint8_t* p = NULL;
-	if (sz < 256) {
-		p = gu_malloc_aligned(pool, 1 + sz, 2);
-		p[0] = (uint8_t) sz;
-	} else {
-		p =	gu_malloc_prefixed(pool, gu_alignof(size_t),
-		                       sizeof(size_t), 1, 1 + sz);
-		((size_t*) p)[-1] = sz;
-		p[0] = 0;
-	}
-	memcpy(&p[1], buf, sz);
-	return (GuString) { (GuWord) (void*) p };
-}
-
-
-
 GuString
 gu_string_buf_freeze(GuStringBuf* sb, GuPool* pool)
 {
 	gu_out_flush(sb->out, NULL);
-	uint8_t* data = gu_buf_data(sb->bbuf);
+	char* data = gu_buf_data(sb->buf);
-	size_t len = gu_buf_length(sb->bbuf);
+	size_t len = gu_buf_length(sb->buf);
-	return gu_utf8_string(data, len, pool);
+
+	char* p = gu_malloc_aligned(pool, len+1, 2);
+	memcpy(p, data, len);
+	p[len] = 0;
+
+	return p;
 }
 
 GuIn*
 gu_string_in(GuString s, GuPool* pool)
 {
-	GuWord w = s.w_;
+	return gu_data_in((uint8_t*) s, strlen(s), pool);
-	uint8_t* buf = NULL;
-	size_t len = 0;
-	if (w & 1) {
-		len = (w & 0xff) >> 1;
-		buf = gu_new_n(uint8_t, len, pool);
-		for (int i = len - 1; i >= 0; i--) {
-			w >>= 8;
-			buf[i] = w & 0xff;
-		}
-	} else {
-		uint8_t* p = (void*) w;
-		len = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		buf = &p[1];
-	}
-	return gu_data_in(buf, len, pool);
-}
-
-static bool
-gu_string_is_long(GuString s) 
-{
-	return !(s.w_ & 1);
-}
-
-bool
-gu_string_is_stable(GuString s)
-{
-	return !gu_string_is_long(s);
-}
-
-static size_t
-gu_string_long_length(GuString s)
-{
-	gu_assert(gu_string_is_long(s));
-	uint8_t* p = (void*) s.w_;
-	uint8_t len = p[0];
-	if (len > 0) {
-		return len;
-	}
-	return ((size_t*) p)[-1];
-}
-
-size_t
-gu_string_length(GuString s)
-{
-	if (gu_string_is_long(s)) {
-		return gu_string_long_length(s);
-	}
-	return (s.w_ & 0xff) >> 1;
-}
-
-static uint8_t*
-gu_string_long_data(GuString s)
-{
-	gu_require(gu_string_is_long(s));
-	uint8_t* p = (void*) s.w_;
-	return &p[1];
 }
 
 GuString
 gu_string_copy(GuString string, GuPool* pool)
 {
-	if (gu_string_is_long(string)) {
+	size_t len = strlen(string);
-		uint8_t* data = gu_string_long_data(string);
+	char* p = gu_malloc_aligned(pool, len+1, 2);
-		size_t len = gu_string_long_length(string);
+	memcpy(p, string, len+1);
-		return gu_utf8_string(data, len, pool);
+	return p;
-	} else {
-		return string;
-	}
 }
 
-
 void
 gu_string_write(GuString s, GuOut* out, GuExn* err)
 {
-	GuWord w = s.w_;
+	gu_out_bytes(out, (uint8_t*) s, strlen(s), err);
-	uint8_t buf[sizeof(GuWord)];
-	uint8_t* src;
-	size_t sz;
-	if (w & 1) {
-		sz = (w & 0xff) >> 1;
-		gu_assert(sz <= sizeof(GuWord));
-		size_t i = sz;
-		while (i > 0) {
-			w >>= 8;
-			buf[--i] = w & 0xff;
-		}
-		src = buf;
-	} else {
-		uint8_t* p = (void*) w;
-		sz = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		src = &p[1];
-	}
-	gu_out_bytes(out, src, sz, err);
 }
 
 GuString
 gu_string_read(size_t len, GuPool* pool, GuIn* in, GuExn* err)
 {
-	uint8_t* buf = alloca(len*4);
+	char* buf = alloca(len*6+1);
-	uint8_t* p   = buf;
+	char* p   = buf;
 	for (size_t i = 0; i < len; i++) {
-		gu_in_utf8_buf(&p, in, err);
+		gu_in_utf8_buf((uint8_t**) &p, in, err);
 	}
-	return gu_utf8_string(buf, p-buf, pool);
+	*p++ = 0;
+
+	p = gu_malloc_aligned(pool, p-buf, 2);
+	strcpy(p, buf);
+
+	return p;
 }
 
 GuString
 gu_string_read_latin1(size_t len, GuPool* pool, GuIn* in, GuExn* err)
 {
-	if (len < GU_MIN(sizeof(GuWord), 128)) {
+	char* p = gu_malloc_aligned(pool, len+1, 2);
-		GuWord w = 0;
+	gu_in_bytes(in, (uint8_t*)p, len, err);
-		for (size_t n = 0; n < len; n++) {
+	p[len] = 0;
-			w = w << 8 | gu_in_u8(in, err);
+	return p;
-		}
-		w = w << 8 | (len << 1) | 1;
-		return (GuString) { w };
-	}
-	uint8_t* p = NULL;
-	if (len < 256) {
-		p = gu_malloc_aligned(pool, 1 + len, 2);
-		p[0] = (uint8_t) len;
-	} else {
-		p =	gu_malloc_prefixed(pool, gu_alignof(size_t),
-		                       sizeof(size_t), 1, 1 + len);
-		((size_t*) p)[-1] = len;
-		p[0] = 0;
-	}
-
-	gu_in_bytes(in, &p[1], len, err);
-	return (GuString) { (GuWord) (void*) p };
 }
 
 GuString
@@ -226,52 +110,24 @@ gu_format_string(GuPool* pool, const char* fmt, ...)
 	return s;
 }
 
-GuString
-gu_str_string(const char* str, GuPool* pool)
-{
-	return gu_utf8_string((const uint8_t*) str, strlen(str), pool);
-}
-
 bool
 gu_string_to_int(GuString s, int *res)
 {
-	GuWord w = s.w_;
-	uint8_t buf[sizeof(GuWord)];
-	char* src;
-	size_t sz;
-	if (w & 1) {
-		sz = (w & 0xff) >> 1;
-		gu_assert(sz <= sizeof(GuWord));
-		size_t i = sz;
-		while (i > 0) {
-			w >>= 8;
-			buf[--i] = w & 0xff;
-		}
-		src = (char*) buf;
-	} else {
-		uint8_t* p = (void*) w;
-		sz = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		src = (char*) &p[1];
-	}
-
-	size_t i = 0;
-	
 	bool neg = false;
-
+	if (*s == '-') {
-	if (src[i] == '-') {
 		neg = true;
-		i++;
+		s++;
 	}
 
-	if (i >= sz)
+	if (*s == 0)
 		return false;
 
 	int n = 0;
-	for (; i < sz; i++) {
+	for (; *s; s++) {
-		if (src[i] < '0' || src[i] > '9')
+		if (*s < '0' || *s > '9')
 			return false;
 
-		n = n * 10 + (src[i] - '0');
+		n = n * 10 + (*s - '0');
 	}
 
 	*res = neg ? -n : n;
@@ -281,54 +137,33 @@ gu_string_to_int(GuString s, int *res)
 bool
 gu_string_to_double(GuString s, double *res)
 {
-	GuWord w = s.w_;
-	uint8_t buf[sizeof(GuWord)];
-	char* src;
-	size_t sz;
-	if (w & 1) {
-		sz = (w & 0xff) >> 1;
-		gu_assert(sz <= sizeof(GuWord));
-		size_t i = sz;
-		while (i > 0) {
-			w >>= 8;
-			buf[--i] = w & 0xff;
-		}
-		src = (char*) buf;
-	} else {
-		uint8_t* p = (void*) w;
-		sz = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		src = (char*) &p[1];
-	}
-
-	size_t i = 0;
-	
 	bool neg = false;
 	bool dec = false;
 	double exp = 1;
 
-	if (src[i] == '-') {
+	if (*s == '-') {
 		neg = true;
-		i++;
+		s++;
 	}
 
-	if (i >= sz)
+	if (*s == 0)
 		return false;
 
 	double d = 0;
-	for (; i < sz; i++) {
+	for (; *s; s++) {
-		if (src[i] == '.') {
+		if (*s == '.') {
 			if (dec) return false;
 
 			dec = true;
 			continue;
 		}
 
-		if (src[i] < '0' || src[i] > '9')
+		if (*s < '0' || *s > '9')
 			return false;
 
 		if (dec) exp = exp * 10;
 
-		d = d * 10 + (src[i] - '0');
+		d = d * 10 + (*s - '0');
 	}
 
 	*res = (neg ? -d : d) / exp;
@@ -338,54 +173,18 @@ gu_string_to_double(GuString s, double *res)
 bool
 gu_string_is_prefix(GuString s1, GuString s2)
 {
-	GuWord w1 = s1.w_;
+	size_t len1 = strlen(s1);
-	uint8_t buf1[sizeof(GuWord)];
+	size_t len2 = strlen(s2);
-	size_t sz1;
-	char* str1;
-	if (w1 & 1) {
-		sz1 = (w1 & 0xff) >> 1;
-		gu_assert(sz1 <= sizeof(GuWord));
-		size_t i = sz1;
-		while (i > 0) {
-			w1 >>= 8;
-			buf1[--i] = w1 & 0xff;
-		}
-		str1 = (char*) buf1;
-	} else {
-		uint8_t* p = (void*) w1;
-		sz1 = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		str1 = (char*) &p[1];
-	}
 
-	GuWord w2 = s2.w_;
+	if (len1 > len2)
-	uint8_t buf2[sizeof(GuWord)];
-	size_t sz2;
-	char* str2;
-	if (w2 & 1) {
-		sz2 = (w2 & 0xff) >> 1;
-		gu_assert(sz2 <= sizeof(GuWord));
-		size_t i = sz2;
-		while (i > 0) {
-			w2 >>= 8;
-			buf2[--i] = w2 & 0xff;
-		}
-		str2 = (char*) buf2;
-	} else {
-		uint8_t* p = (void*) w2;
-		sz2 = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		str2 = (char*) &p[1];
-	}
-
-	
-	if (sz1 > sz2)
 		return false;
 
-	for (size_t sz = sz1; sz--; sz > 0) {
+	for (size_t len = len1; len--; len > 0) {
-		if (*str1 != *str2)
+		if (*s1 != *s2)
 			return false;
-			
+
-		str1++;
+		s1++;
-		str2++;
+		s2++;
 	}
 
 	return true;
@@ -394,108 +193,23 @@ gu_string_is_prefix(GuString s1, GuString s2)
 GuHash
 gu_string_hash(GuHash h, GuString s)
 {
-	if (s.w_ & 1) {
+	return gu_hash_bytes(h, (uint8_t*)s, strlen(s));
-		return h*101 + s.w_;
-	}
-	size_t len = gu_string_length(s);
-	uint8_t* data = gu_string_long_data(s);
-	return gu_hash_bytes(h, data, len);
-}
-
-bool
-gu_string_eq(GuString s1, GuString s2)
-{
-	if (s1.w_ == s2.w_) {
-		return true;
-	} else if (gu_string_is_long(s1) && gu_string_is_long(s2)) {
-		size_t len1 = gu_string_long_length(s1);
-		size_t len2 = gu_string_long_length(s2);
-		if (len1 != len2) {
-			return false;
-		}
-		uint8_t* data1 = gu_string_long_data(s1);
-		uint8_t* data2 = gu_string_long_data(s2);
-		return (memcmp(data1, data2, len1) == 0);
-	}
-	return false;
-
 }
 
 static bool
 gu_string_eq_fn(GuEquality* self, const void* p1, const void* p2)
 {
 	(void) self;
-	const GuString* sp1 = p1;
+	return strcmp((GuString) p1, (GuString) p2) == 0;
-	const GuString* sp2 = p2;
-	return gu_string_eq(*sp1, *sp2);
 }
 
 GuEquality gu_string_equality[1] = { { gu_string_eq_fn } };
 
-int
-gu_string_cmp(GuString s1, GuString s2)
-{
-	uint8_t buf1[sizeof(GuWord)];
-	char* src1;
-	size_t sz1;
-	if (s1.w_ & 1) {
-		sz1 = (s1.w_ & 0xff) >> 1;
-		gu_assert(sz1 <= sizeof(GuWord));
-		size_t i = sz1;
-		while (i > 0) {
-			s1.w_ >>= 8;
-			buf1[--i] = s1.w_ & 0xff;
-		}
-		src1 = (char*) buf1;
-	} else {
-		uint8_t* p = (void*) s1.w_;
-		sz1 = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		src1 = (char*) &p[1];
-	}
-
-	uint8_t buf2[sizeof(GuWord)];
-	char* src2;
-	size_t sz2;
-	if (s2.w_ & 1) {
-		sz2 = (s2.w_ & 0xff) >> 1;
-		gu_assert(sz2 <= sizeof(GuWord));
-		size_t i = sz2;
-		while (i > 0) {
-			s2.w_ >>= 8;
-			buf2[--i] = s2.w_ & 0xff;
-		}
-		src2 = (char*) buf2;
-	} else {
-		uint8_t* p = (void*) s2.w_;
-		sz2 = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		src2 = (char*) &p[1];
-	}
-
-	for (size_t i = 0; ; i++) {
-		if (sz1 == i && i == sz2)
-			break;
-		
-		if (sz1 <= i)
-			return -1;
-		if (i >= sz2)
-			return 1;
-
-		if (src1[i] > src2[i])
-			return 1;
-		else if (src1[i] < src2[i])
-			return -1;
-	}
-
-	return 0;
-}
-
 static int
 gu_string_cmp_fn(GuOrder* self, const void* p1, const void* p2)
 {
 	(void) self;
-	const GuString* sp1 = p1;
+	return strcmp((GuString) p1, (GuString) p2);
-	const GuString* sp2 = p2;
-	return gu_string_cmp(*sp1, *sp2);
 }
 
 GuOrder gu_string_order[1] = { { gu_string_cmp_fn } };
@@ -504,8 +218,7 @@ static GuHash
 gu_string_hasher_hash(GuHasher* self, const void* p)
 {
 	(void) self;
-	const GuString* sp = p;
+	return gu_string_hash(0, (GuString) p);
-	return gu_string_hash(0, *sp);
 }
 
 GuHasher gu_string_hasher[1] = {
@@ -516,5 +229,5 @@ GuHasher gu_string_hasher[1] = {
 };
 
 
-GU_DEFINE_TYPE(GuString, GuOpaque, _);
+GU_DEFINE_KIND(GuString, pointer);
 GU_DEFINE_KIND(GuStringMap, GuMap);

src/runtime/c/gu/string.h

@@ -1,22 +1,3 @@
-/* 
- * Copyright 2011 University of Helsinki.
- *   
- * This file is part of libgu.
- * 
- * Libgu is free software: you can redistribute it and/or modify it under
- * the terms of the GNU Lesser General Public License as published by the
- * Free Software Foundation, either version 3 of the License, or (at your
- * option) any later version.
- * 
- * Libgu is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
- * License for more details.
- * 
- * You should have received a copy of the GNU Lesser General Public
- * License along with libgu. If not, see <http://www.gnu.org/licenses/>.
- */
-
 #ifndef GU_STRING_H_
 #define GU_STRING_H_
 
@@ -24,9 +5,7 @@
 #include <gu/in.h>
 #include <gu/out.h>
 
-typedef GuOpaque() GuString;
+typedef const char* GuString;
-
-extern const GuString gu_empty_string;
 
 GuString
 gu_string_copy(GuString string, GuPool* pool);
@@ -43,12 +22,6 @@ gu_string_read_latin1(size_t len, GuPool* pool, GuIn* in, GuExn* err);
 GuIn*
 gu_string_in(GuString string, GuPool* pool);
 
-bool
-gu_string_is_stable(GuString string);
-
-GuString
-gu_ucs_string(const GuUCS* ubuf, size_t len, GuPool* pool);
-
 typedef struct GuStringBuf GuStringBuf;
 
 GuStringBuf*
@@ -66,34 +39,21 @@ gu_format_string_v(const char* fmt, va_list args, GuPool* pool);
 GuString
 gu_format_string(GuPool* pool, const char* fmt, ...);
 
-GuString
-gu_str_string(const char* str, GuPool* pool);
-
 bool
 gu_string_to_int(GuString s, int *res);
 
 bool
 gu_string_to_double(GuString s, double *res);
 
-
 bool
 gu_string_is_prefix(GuString s1, GuString s2);
 
-size_t
-gu_string_length(GuString s);
-
 #endif // GU_STRING_H_
 
 #if defined(GU_FUN_H_) && !defined(GU_STRING_H_FUN_)
 #define GU_STRING_H_FUN_
-bool
-gu_string_eq(GuString s1, GuString s2);
-
 extern GuEquality gu_string_equality[1];
 
-int
-gu_string_cmp(GuString s1, GuString s2);
-
 extern GuOrder gu_string_order[1];
 #endif
 
@@ -110,7 +70,7 @@ extern GuHasher gu_string_hasher[1];
 # ifndef GU_STRING_H_TYPE_
 #  define GU_STRING_H_TYPE_
 
-extern GU_DECLARE_TYPE(GuString, GuOpaque);
+extern GU_DECLARE_KIND(GuString);
 # endif
 
 # if defined(GU_MAP_H_TYPE_) && !defined(GU_STRING_H_MAP_TYPE_)
@@ -132,8 +92,6 @@ typedef GuType_GuMap GuType_GuStringMap;
 #define GU_STRING_H_SEQ_
 
 typedef GuSeq GuStrings;
-// typedef GuBuf GuStringBuf;
-
 #endif
 
 

src/runtime/c/pgf/data.c

@@ -15,7 +15,7 @@ pgf_tokens_equal(PgfTokens* t1, PgfTokens* t2)
 	for (size_t i = 0; i < len1; i++) {
 		GuString s1 = gu_seq_get(t1, PgfToken, i);
 		GuString s2 = gu_seq_get(t2, PgfToken, i);
-		if (!gu_string_eq(s1, s2)) {
+		if (strcmp(s1, s2) != 0) {
 			return false;
 		}
 	}
@@ -51,7 +51,9 @@ GU_DEFINE_TYPE(PgfMetaChildMap, GuMap,
 
 GU_DEFINE_TYPE(PgfAbsCat, abstract);
 
+static GuString empty_string = "";
+
 GU_DEFINE_TYPE(
-	PgfPrintNames, PgfCIdMap, gu_type(GuString), &gu_empty_string);
+	PgfPrintNames, PgfCIdMap, gu_type(GuString), &empty_string);
 
 GU_DEFINE_TYPE(PgfConcr, abstract);

src/runtime/c/pgf/data.h

@@ -190,7 +190,7 @@ typedef struct {
 typedef PgfSymbolIdx PgfSymbolCat, PgfSymbolLit, PgfSymbolVar;
 
 typedef struct {
-	PgfToken token;
+	char token[0];   // a flexible array that contains the token
 } PgfSymbolKS;
 
 typedef struct PgfSymbolKP

src/runtime/c/pgf/expr.c

@@ -152,7 +152,7 @@ struct PgfExprParser {
 	GuPool* expr_pool;
 	GuPool* tmp_pool;
 	PGF_TOKEN_TAG token_tag;
-	GuCharBuf* token_value;
+	GuBuf* token_value;
 	int ch;
 };
 
@@ -232,7 +232,7 @@ pgf_expr_parser_token(PgfExprParser* parser)
 		parser->token_tag = PGF_TOKEN_WILD;
 		break;
 	default: {
-		GuCharBuf* chars = gu_new_buf(char, parser->tmp_pool);
+		GuBuf* chars = gu_new_buf(char, parser->tmp_pool);
 
 		if (isalpha(parser->ch)) {
 			while (isalnum(parser->ch) || 
@@ -241,6 +241,7 @@ pgf_expr_parser_token(PgfExprParser* parser)
 				gu_buf_push(chars, char, parser->ch);
 				pgf_expr_parser_getc(parser);
 			}
+			gu_buf_push(chars, char, 0);
 			parser->token_tag   = PGF_TOKEN_IDENT;
 			parser->token_value = chars;
 		} else if (isdigit(parser->ch)) {
@@ -257,9 +258,11 @@ pgf_expr_parser_token(PgfExprParser* parser)
 					gu_buf_push(chars, char, parser->ch);
 					pgf_expr_parser_getc(parser);
 				}
+				gu_buf_push(chars, char, 0);
 				parser->token_tag   = PGF_TOKEN_FLT;
 				parser->token_value = chars;
 			} else {
+				gu_buf_push(chars, char, 0);
 				parser->token_tag   = PGF_TOKEN_INT;
 				parser->token_value = chars;
 			}
@@ -273,6 +276,7 @@ pgf_expr_parser_token(PgfExprParser* parser)
 			
 			if (parser->ch == '"') {
 				pgf_expr_parser_getc(parser);
+				gu_buf_push(chars, char, 0);
 				parser->token_tag   = PGF_TOKEN_STR;
 				parser->token_value = chars;
 			}
@@ -341,18 +345,20 @@ pgf_expr_parser_term(PgfExprParser* parser)
 					            0);
 	}
 	case PGF_TOKEN_IDENT: {
-		char* str = 
+		PgfCId id = gu_buf_data(parser->token_value);
-			gu_char_buf_str(parser->token_value, parser->tmp_pool);
-		PgfCId id = gu_str_string(str, parser->expr_pool);
 		pgf_expr_parser_token(parser);
-		return gu_new_variant_i(parser->expr_pool,
+		PgfExpr e;
-					PGF_EXPR_FUN,
+		PgfExprFun* fun =
-					PgfExprFun,
+			gu_new_flex_variant(PGF_EXPR_FUN,
-					id);
+			                    PgfExprFun,
+                                fun, strlen(id)+1,
+                                &e, parser->expr_pool);
+        strcpy(fun->fun, id);
+		return e;
 	}
 	case PGF_TOKEN_INT: {
 		char* str = 
-			gu_char_buf_str(parser->token_value, parser->tmp_pool);
+			gu_buf_data(parser->token_value);
 		int n = atoi(str);
 		pgf_expr_parser_token(parser);
 		PgfLiteral lit = 
@@ -367,22 +373,23 @@ pgf_expr_parser_term(PgfExprParser* parser)
 	}
 	case PGF_TOKEN_STR: {
 		char* str =
-			gu_char_buf_str(parser->token_value, parser->tmp_pool);
+			gu_buf_data(parser->token_value);
-		GuString s = gu_str_string(str, parser->expr_pool);
 		pgf_expr_parser_token(parser);
-		PgfLiteral lit = 
+		PgfLiteral lit;
-			gu_new_variant_i(parser->expr_pool,
+		PgfLiteralStr* plit = 
-			                 PGF_LITERAL_STR,
+			gu_new_flex_variant(PGF_LITERAL_STR,
-			                 PgfLiteralStr,
+			                    PgfLiteralStr,
-			                 s);
+			                    val, strlen(str)+1,
+			                    &lit, parser->expr_pool);
+		strcpy(plit->val, str);
 		return gu_new_variant_i(parser->expr_pool,
-					PGF_EXPR_LIT,
+		                        PGF_EXPR_LIT,
-					PgfExprLit,
+		                        PgfExprLit,
-					lit);
+		                        lit);
 	}
 	case PGF_TOKEN_FLT: {
 		char* str = 
-			gu_char_buf_str(parser->token_value, parser->tmp_pool);
+			gu_buf_data(parser->token_value);
 		double d = atof(str);
 		pgf_expr_parser_token(parser);
 		PgfLiteral lit = 
@@ -442,12 +449,11 @@ pgf_expr_parser_bind(PgfExprParser* parser, GuBuf* binds)
 
 	for (;;) {
 		if (parser->token_tag == PGF_TOKEN_IDENT) {
-			char* str = 
+			var =
-				gu_char_buf_str(parser->token_value, parser->tmp_pool);
+				gu_string_copy(gu_buf_data(parser->token_value), parser->expr_pool);
-			var = gu_str_string(str, parser->expr_pool);
 			pgf_expr_parser_token(parser);
 		} else if (parser->token_tag == PGF_TOKEN_WILD) {
-			var = gu_str_string("_", parser->expr_pool);
+			var = "_";
 			pgf_expr_parser_token(parser);
 		} else {
 			return false;
@@ -562,12 +568,11 @@ pgf_expr_parser_hypos(PgfExprParser* parser, GuBuf* hypos)
 		}
 
 		if (parser->token_tag == PGF_TOKEN_IDENT) {
-			char* str = 
+			var =
-				gu_char_buf_str(parser->token_value, parser->tmp_pool);
+				gu_string_copy(gu_buf_data(parser->token_value), parser->expr_pool);
-			var = gu_str_string(str, parser->expr_pool);
 			pgf_expr_parser_token(parser);
 		} else if (parser->token_tag == PGF_TOKEN_WILD) {
-			var = gu_str_string("_", parser->expr_pool);
+			var = "_";
 			pgf_expr_parser_token(parser);
 		} else {
 			return false;
@@ -603,9 +608,8 @@ pgf_expr_parser_atom(PgfExprParser* parser)
 	if (parser->token_tag != PGF_TOKEN_IDENT)
 		return NULL;
 
-	char* str =
+	PgfCId cid =
-		gu_char_buf_str(parser->token_value, parser->tmp_pool);
+		gu_string_copy(gu_buf_data(parser->token_value), parser->expr_pool);
-	PgfCId cid = gu_str_string(str, parser->expr_pool);
 	pgf_expr_parser_token(parser);
 
 	GuBuf* args = gu_new_buf(PgfExpr, parser->tmp_pool);
@@ -663,7 +667,7 @@ pgf_expr_parser_type(PgfExprParser* parser)
 			} else {
 				PgfHypo* hypo = gu_buf_extend(hypos);
 				hypo->bind_type = PGF_BIND_TYPE_EXPLICIT;
-				hypo->cid = gu_str_string("_", parser->expr_pool);
+				hypo->cid = "_";
 				hypo->type = NULL;
 			}
 
@@ -699,7 +703,7 @@ pgf_expr_parser_type(PgfExprParser* parser)
 
 			PgfHypo* hypo = gu_buf_extend(hypos);
 			hypo->bind_type = PGF_BIND_TYPE_EXPLICIT;
-			hypo->cid = gu_str_string("_", parser->expr_pool);
+			hypo->cid = "_";
 			hypo->type = type;
 		}
 	}
@@ -761,7 +765,7 @@ pgf_literal_eq(PgfLiteral lit1, PgfLiteral lit2)
 	case PGF_LITERAL_STR: {
 		PgfLiteralStr* lit1 = ei1.data;
 		PgfLiteralStr* lit2 = ei2.data;
-        return gu_string_eq(lit1->val, lit2->val);
+        return strcmp(lit1->val, lit2->val) == 0;
     }
     case PGF_LITERAL_INT: {
 		PgfLiteralInt* lit1 = ei1.data;
@@ -793,7 +797,7 @@ pgf_expr_eq(PgfExpr e1, PgfExpr e2)
 	case PGF_EXPR_ABS: {
 		PgfExprAbs* abs1 = ei1.data;
 		PgfExprAbs* abs2 = ei2.data;
-		return gu_string_eq(abs1->id, abs2->id) &&
+		return strcmp(abs1->id, abs2->id) == 0 &&
 		       pgf_expr_eq(abs1->body, abs2->body);
 	}
 	case PGF_EXPR_APP: {
@@ -815,7 +819,7 @@ pgf_expr_eq(PgfExpr e1, PgfExpr e2)
 	case PGF_EXPR_FUN: {
 		PgfExprFun* fun1 = ei1.data;
 		PgfExprFun* fun2 = ei2.data;
-		return gu_string_eq(fun1->fun, fun2->fun);
+		return strcmp(fun1->fun, fun2->fun) == 0;
 	}
 	case PGF_EXPR_VAR: {
 		PgfExprVar* var1 = ei1.data;
@@ -1076,9 +1080,8 @@ pgf_print_hypo(PgfHypo *hypo, PgfPrintContext* ctxt, int prec,
         gu_puts(")", out, err);
     } else {
         GuPool* tmp_pool = gu_new_pool();
-        GuString tmp = gu_str_string("_", tmp_pool);
+
-        
+        if (strcmp(hypo->cid, "_") != 0) {
-        if (!gu_string_eq(hypo->cid, tmp)) {
             gu_puts("(", out, err);
             gu_string_write(hypo->cid, out, err);
             gu_puts(" : ", out, err);
@@ -1158,14 +1161,14 @@ pgf_type_eq(PgfType* t1, PgfType* t2)
 		if (hypo1->bind_type != hypo2->bind_type)
 			return false;
 			
-		if (!gu_string_eq(hypo1->cid, hypo2->cid))
+		if (strcmp(hypo1->cid, hypo2->cid) != 0)
 			return false;
 			
 		if (!pgf_type_eq(hypo1->type, hypo2->type))
 			return false;
 	}
     
-	if (!gu_string_eq(t1->cid, t2->cid))
+	if (strcmp(t1->cid, t2->cid) != 0)
 		return false;
 
 	if (t1->n_exprs != t2->n_exprs)

src/runtime/c/pgf/expr.h

@@ -37,7 +37,7 @@ typedef enum {
 } PgfLiteralTag;
 
 typedef struct {
-	GuString val;
+	char val[0];  // a flexible array that contains the value
 } PgfLiteralStr;
 
 typedef struct {
@@ -102,7 +102,7 @@ typedef struct {
 } PgfExprMeta;
 
 typedef struct {
-	PgfCId fun;
+	char fun[0];
 } PgfExprFun;
 
 typedef struct {

src/runtime/c/pgf/graphviz.c

@@ -112,7 +112,6 @@ typedef struct {
 	size_t level;
 	GuBuf* internals;
 	GuBuf* leaves;
-	GuString wildcard;
 } PgfBracketLznState;
 
 static void
@@ -167,7 +166,7 @@ pgf_bracket_lzn_begin_phrase(PgfLinFuncs** funcs, PgfCId cat, int fid, int linde
 {
 	PgfBracketLznState* state = gu_container(funcs, PgfBracketLznState, funcs);
 
-	if (gu_string_eq(cat, state->wildcard))
+	if (strcmp(cat, "_") == 0)
 		return;
 	
 	state->level++;
@@ -203,7 +202,7 @@ pgf_bracket_lzn_end_phrase(PgfLinFuncs** funcs, PgfCId cat, int fid, int lindex,
 {
 	PgfBracketLznState* state = gu_container(funcs, PgfBracketLznState, funcs);
 
-	if (gu_string_eq(cat, state->wildcard))
+	if (strcmp(cat, "_") == 0)
 		return;
 
 	state->level--;
@@ -281,7 +280,6 @@ pgf_graphviz_parse_tree(PgfConcr* concr, PgfExpr expr, GuOut* out, GuExn* err)
 	state.level     = -1;
 	state.internals = gu_new_buf(GuBuf*, tmp_pool);
 	state.leaves    = gu_new_buf(PgfParseNode*, tmp_pool);
-	state.wildcard  = gu_str_string("_", tmp_pool);
 	pgf_lzr_linearize(concr, ctree, 0, &state.funcs);
 
 	size_t len = gu_buf_length(state.internals);

src/runtime/c/pgf/jit.c

@@ -201,7 +201,7 @@ pgf_jit_predicate(PgfJitState* state, PgfCIdMap* abscats,
 				
 				// call the predicate for the category in hypo->type->cid
 				PgfAbsCat* arg =
-					gu_map_get(abscats, &hypo->type->cid, PgfAbsCat*);
+					gu_map_get(abscats, hypo->type->cid, PgfAbsCat*);
 
 #ifdef PGF_JIT_DEBUG
 				gu_puts("    CALL ", wtr, err);
@@ -314,7 +314,7 @@ pgf_jit_done(PgfJitState* state, PgfAbstr* abstr)
 		PgfCallPatch* patch =
 			gu_buf_index(state->patches, PgfCallPatch, i);
 		PgfAbsCat* arg =
-			gu_map_get(abstr->cats, &patch->cid, PgfAbsCat*);
+			gu_map_get(abstr->cats, patch->cid, PgfAbsCat*);
 		gu_assert(arg != NULL);
 
 		jit_patch_calli(patch->ref,(jit_insn*) arg->predicate);

src/runtime/c/pgf/lexer.c

@@ -108,7 +108,7 @@ pgf_new_simple_lexer(GuIn *in, GuPool *pool)
 {
 	PgfSimpleLexer* lexer = gu_new(PgfSimpleLexer, pool);
 	lexer->base.read_token = pgf_simple_lexer_read_token;
-	lexer->base.tok = gu_empty_string;
+	lexer->base.tok = "";
 	lexer->in = in;
 	lexer->pool = pool;
 	lexer->ucs = ' ';	

src/runtime/c/pgf/linearizer.c

@@ -45,12 +45,12 @@ pgf_lzr_index(PgfConcr* concr,
 	case PGF_PRODUCTION_APPLY: {
 		PgfProductionApply* papply = data;
 		PgfCncOverloadMap* overl_table =
-			gu_map_get(concr->fun_indices, &papply->fun->absfun->name,
+			gu_map_get(concr->fun_indices, papply->fun->absfun->name,
 				PgfCncOverloadMap*);
 		if (!overl_table) {
 			overl_table = gu_map_type_new(PgfCncOverloadMap, pool);
 			gu_map_put(concr->fun_indices,
-				&papply->fun->absfun->name, PgfCncOverloadMap*, overl_table);
+				papply->fun->absfun->name, PgfCncOverloadMap*, overl_table);
 		}
 		pgf_lzr_add_overl_entry(overl_table, ccat, papply, pool);
 		break;
@@ -227,11 +227,12 @@ pgf_lzn_resolve_def(PgfLzn* lzn, PgfCncFuns* lindefs, GuString s, GuPool* pool)
 					   PgfCncTreeLit,
 					   &lit, pool);
 	clit->fid = lzn->fid++;
-	clit->lit =
+	PgfLiteralStr* lit_str =
-		gu_new_variant_i(pool,
+		gu_new_flex_variant(PGF_LITERAL_STR,
-					 PGF_LITERAL_STR,
+					        PgfLiteralStr,
-					 PgfLiteralStr,
+					        val, strlen(s),
-					 s);
+					        &clit->lit, pool);
+	strcpy((char*) lit_str->val, (char*) s);
 
 	if (lindefs == NULL)
 		return lit;
@@ -322,8 +323,7 @@ pgf_lzn_resolve(PgfLzn* lzn, PgfExpr expr, PgfCCat* ccat, GuPool* pool)
 					goto done;
 				}
 
-				GuString s = gu_str_string("?", pool);
+				ret = pgf_lzn_resolve_def(lzn, ccat->lindefs, "?", pool);
-				ret = pgf_lzn_resolve_def(lzn, ccat->lindefs, s, pool);
 				goto done;
 			}
 		}
@@ -331,7 +331,7 @@ pgf_lzn_resolve(PgfLzn* lzn, PgfExpr expr, PgfCCat* ccat, GuPool* pool)
 			PgfExprFun* efun = i.data;
 
 			PgfCncOverloadMap* overl_table =
-				gu_map_get(lzn->concr->fun_indices, &efun->fun, PgfCncOverloadMap*);
+				gu_map_get(lzn->concr->fun_indices, efun->fun, PgfCncOverloadMap*);
 			if (overl_table == NULL) {
 				if (ccat != NULL && ccat->lindefs == NULL) {
 					goto done;
@@ -345,7 +345,7 @@ pgf_lzn_resolve(PgfLzn* lzn, PgfExpr expr, PgfCCat* ccat, GuPool* pool)
 				gu_putc('[', out, err);
 				gu_string_write(efun->fun, out, err);
 				gu_putc(']', out, err);
-				GuString s = gu_string_buf_freeze(sbuf, pool);
+				GuString s = gu_string_buf_freeze(sbuf, tmp_pool);
 
 				if (ccat != NULL) {
 					ret = pgf_lzn_resolve_def(lzn, ccat->lindefs, s, pool);
@@ -356,10 +356,11 @@ pgf_lzn_resolve(PgfLzn* lzn, PgfExpr expr, PgfCCat* ccat, GuPool* pool)
 									   &ret, pool);
 					clit->fid = lzn->fid++;
 					PgfLiteralStr* lit = 
-						gu_new_variant(PGF_LITERAL_STR,
+						gu_new_flex_variant(PGF_LITERAL_STR,
-									   PgfLiteralStr,
+									        PgfLiteralStr,
-									   &clit->lit, pool);
+									        val, strlen(s)+1,
-					lit->val = s;
+									        &clit->lit, pool);
+					strcpy(lit->val, s);
 				}
 
 				gu_pool_free(tmp_pool);
@@ -557,7 +558,7 @@ pgf_lzr_linearize(PgfConcr* concr, PgfCncTree ctree, size_t lin_idx, PgfLinFuncs
 		if (fns->begin_phrase) {
 			fns->begin_phrase(fnsp,
 							  cat, flit->fid, 0,
-							  gu_empty_string);
+							  "");
 		}
 
 		if (fns->expr_literal) {
@@ -567,7 +568,7 @@ pgf_lzr_linearize(PgfConcr* concr, PgfCncTree ctree, size_t lin_idx, PgfLinFuncs
 		if (fns->end_phrase) {
 			fns->end_phrase(fnsp,
 							cat, flit->fid, 0,
-							gu_empty_string);
+							"");
 		}
 
 		break;
@@ -697,7 +698,7 @@ pgf_get_tokens(PgfSequence* seq, uint16_t seq_idx, GuPool* pool)
 	pgf_lzr_linearize_sequence(NULL, NULL, seq, seq_idx, &flin.funcs);
 
 	GuString tokens = gu_ok(err) ? gu_string_buf_freeze(sbuf, pool)
-	                             : gu_empty_string;
+	                             : "";
 
 	gu_pool_free(tmp_pool);
 

src/runtime/c/pgf/literals.c

@@ -39,10 +39,11 @@ pgf_match_string_lit(PgfConcr* concr, PgfItem* item, PgfToken tok,
 						   PgfExprLit,
 						   &ep->expr, pool);
 		PgfLiteralStr *lit_str =
-			gu_new_variant(PGF_LITERAL_STR,
+			gu_new_flex_variant(PGF_LITERAL_STR,
-						   PgfLiteralStr,
+						        PgfLiteralStr,
-						   &expr_lit->lit, pool);
+						        val, strlen(sks->token)+1,
-		lit_str->val = sks->token;
+						        &expr_lit->lit, pool);
+		strcpy(lit_str->val, sks->token);
 
 		*out_ep = ep;
 		accepted = false;
@@ -185,12 +186,10 @@ pgf_match_name_lit(PgfConcr* concr, PgfItem* item, PgfToken tok,
 
 	GuExn* err = gu_new_exn(NULL, gu_kind(type), tmp_pool);
 	
-	GuString hyp = gu_str_string("-", tmp_pool);
-	
 	bool iscap = false;
-	if (gu_string_eq(tok, hyp)) {
+	if (strcmp(tok, "-") == 0) {
 		iscap = true;
-	} else if (!gu_string_eq(tok, gu_empty_string)) {
+	} else if (*tok) {
 		GuIn* in = gu_string_in(tok, tmp_pool);
 		iscap = iswupper(gu_in_utf8(in, err));
 	}
@@ -218,21 +217,24 @@ pgf_match_name_lit(PgfConcr* concr, PgfItem* item, PgfToken tok,
 			gu_new_variant(PGF_EXPR_APP,
 			               PgfExprApp,
 			               &ep->expr, pool);
+		GuString con = "MkSymb";
 		PgfExprFun *expr_fun =
-			gu_new_variant(PGF_EXPR_FUN,
+			gu_new_flex_variant(PGF_EXPR_FUN,
-			               PgfExprFun,
+			                    PgfExprFun,
-			               &expr_app->fun, pool);
+			                    fun, strlen(con)+1,
-		expr_fun->fun = gu_str_string("MkSymb", pool);
+			                    &expr_app->fun, pool);
+		strcpy(expr_fun->fun, con);
 		PgfExprLit *expr_lit =
 			gu_new_variant(PGF_EXPR_LIT,
 			               PgfExprLit,
 			               &expr_app->arg, pool);
+		GuString val = gu_string_buf_freeze(sbuf, tmp_pool);
 		PgfLiteralStr *lit_str =
-			gu_new_variant(PGF_LITERAL_STR,
+			gu_new_flex_variant(PGF_LITERAL_STR,
-			               PgfLiteralStr,
+			                    PgfLiteralStr,
-			               &expr_lit->lit, pool);
+			                    val, strlen(val)+1,
-		lit_str->val = gu_string_buf_freeze(sbuf, pool);
+			                    &expr_lit->lit, pool);
-
+        strcpy(lit_str->val, val);
 		*out_ep = ep;
 	} else {
 		*out_ep = NULL;

src/runtime/c/pgf/parser.c

@@ -145,24 +145,7 @@ GU_DEFINE_TYPE(PgfLeftcornerTokIdx, GuStringMap,
 static PgfSymbol
 pgf_prev_extern_sym(PgfSymbol sym)
 {
-	GuVariantInfo i = gu_variant_open(sym);
+	return *(((PgfSymbol*) gu_variant_data(sym))-1);
-	switch (i.tag) {
-	case PGF_SYMBOL_CAT:
-		return *((PgfSymbol*) (((PgfSymbolCat*) i.data)+1));
-	case PGF_SYMBOL_KP:
-		return *((PgfSymbol*) (((PgfSymbolKP*) i.data)+1));
-	case PGF_SYMBOL_KS:
-		return *((PgfSymbol*) (((PgfSymbolKS*) i.data)+1));
-	case PGF_SYMBOL_LIT:
-		return *((PgfSymbol*) (((PgfSymbolLit*) i.data)+1));
-	case PGF_SYMBOL_VAR:
-		return *((PgfSymbol*) (((PgfSymbolVar*) i.data)+1));
-	case PGF_SYMBOL_NE:
-		return *((PgfSymbol*) (((PgfSymbolNE*) i.data)+1));
-	default:
-		gu_impossible();
-		return gu_null_variant;
-	}
 }
 
 size_t
@@ -1126,19 +1109,19 @@ pgf_parsing_meta_scan(PgfParseState* before, PgfParseState* after,
 	                  PgfItem* meta_item, prob_t meta_prob)
 {
 	PgfToken tok = after->ts->fn->get_token(after->ts);
-	
+
-	if (!gu_string_eq(tok, gu_empty_string)) {	
+	if (*tok == 0) {	
 		PgfItem* item = pgf_item_copy(meta_item, before->ps->pool, before->ps);
 		item->inside_prob += meta_prob;
 
 		PgfSymbol prev = item->curr_sym;
 		PgfSymbolKS* sks = (PgfSymbolKS*)
 			gu_alloc_variant(PGF_SYMBOL_KS,
-							 sizeof(PgfSymbolKS)+sizeof(PgfSymbol),
+							 sizeof(PgfSymbol)+sizeof(PgfSymbolKS)+strlen(tok)+1,
 							 gu_alignof(PgfSymbolKS),
 							 &item->curr_sym, after->ps->pool);
-		*((PgfSymbol*)(sks+1)) = prev;
+		*(((PgfSymbol*) sks)-1) = prev;
-		sks->token = tok;
+		strcpy((char*) sks->token, (char*) tok);
 
 		gu_buf_heap_push(before->agenda, &pgf_item_prob_order, &item);
 	}
@@ -1162,7 +1145,7 @@ pgf_parsing_meta_predict(GuMapItor* fn, const void* key, void* value, GuExn* err
     PgfItem* meta_item  = clo->meta_item;
 
     PgfCncCat* cnccat =
-		gu_map_get(state->ps->concr->cnccats, &abscat->name, PgfCncCat*);
+		gu_map_get(state->ps->concr->cnccats, abscat->name, PgfCncCat*);
 	if (cnccat == NULL)
 		return;
 
@@ -1193,7 +1176,7 @@ pgf_parsing_meta_predict(GuMapItor* fn, const void* key, void* value, GuExn* err
 								 sizeof(PgfSymbolCat)+sizeof(PgfSymbol),
 								 gu_alignof(PgfSymbolCat),
 								 &item->curr_sym, state->ps->pool);
-			*((PgfSymbol*)(scat+1)) = prev;
+			*(((PgfSymbol*)scat)-1) = prev;
 			scat->d = nargs;
 			scat->r = lin_idx;
 		
@@ -1342,6 +1325,10 @@ pgf_parsing_symbol(PgfParseState* before, PgfParseState* after,
 		pgf_item_free(before, after, item);
 		break;
 	}
+	case PGF_SYMBOL_BIND: {
+		pgf_item_free(before, after, item);
+		break;
+	}
 	default:
 		gu_impossible();
 	}
@@ -1412,7 +1399,7 @@ pgf_parsing_item(PgfParseState* before, PgfParseState* after, PgfItem* item)
 		} else {
 			PgfToken tok = (after != NULL)
 			    ? after->ts->fn->get_token(after->ts)
-			    : gu_empty_string;
+			    : "";
 
 			PgfExprProb *ep = NULL;
 			bool accepted = 
@@ -1428,11 +1415,11 @@ pgf_parsing_item(PgfParseState* before, PgfParseState* after, PgfItem* item)
 					PgfSymbol prev = item->curr_sym;
 					PgfSymbolKS* sks = (PgfSymbolKS*)
 						gu_alloc_variant(PGF_SYMBOL_KS,
-										 sizeof(PgfSymbolKS)+sizeof(PgfSymbol),
+										 sizeof(PgfSymbol)+sizeof(PgfSymbolKS)+strlen(tok)+1,
 										 gu_alignof(PgfSymbolKS),
 										 &item->curr_sym, after->ps->pool);
-					*((PgfSymbol*)(sks+1)) = prev;
+					*(((PgfSymbol*) sks)-1) = prev;
-					sks->token = tok;
+					strcpy((char*) sks->token, (char*) tok);
 
 					item->seq_idx++;
 					pgf_parsing_add_transition(before, after, tok, item);
@@ -1546,9 +1533,7 @@ pgf_parsing_proceed(PgfParseState* state)
 static prob_t
 pgf_parsing_default_beam_size(PgfConcr* concr)
 {
-	GuPool* tmp_pool = gu_new_pool();
+	PgfLiteral lit = gu_map_get(concr->cflags, "beam_size", PgfLiteral);
-	PgfCId flag_name = gu_str_string("beam_size", tmp_pool);
-	PgfLiteral lit = gu_map_get(concr->cflags, &flag_name, PgfLiteral);
 	
 	if (gu_variant_is_null(lit))
 		return 0;
@@ -1677,7 +1662,7 @@ typedef struct {
 static bool
 pgf_real_match_token(PgfTokenState* ts, PgfToken tok, PgfItem* item)
 {
-	return gu_string_eq(gu_container(ts, PgfRealTokenState, ts)->tok, tok);
+	return strcmp(gu_container(ts, PgfRealTokenState, ts)->tok, tok) == 0;
 }
 
 static PgfToken
@@ -1707,7 +1692,7 @@ pgf_parser_next_state(PgfParseState* prev, PgfToken tok)
 		pgf_new_token_state(PgfRealTokenState, prev->ps->pool);
 	ts->tok = tok;
     ts->lexicon_idx = gu_map_get(prev->ps->concr->leftcorner_tok_idx,
-                                 &tok, PgfProductionIdx*);	
+                                 tok, PgfProductionIdx*);	
 	if (ts->lexicon_idx != NULL) {
 		PgfLexiconFn clo = { { pgf_parser_compute_lexicon_prob }, &ts->ts };
 		gu_map_iter(ts->lexicon_idx, &clo.fn, NULL);
@@ -1758,7 +1743,7 @@ pgf_prefix_match_token(PgfTokenState* ts0, PgfToken tok, PgfItem* item)
 
 static PgfToken
 pgf_prefix_get_token(PgfTokenState* ts) {
-	return gu_empty_string;
+	return "";
 }
 
 static PgfProductionIdx*
@@ -2165,7 +2150,7 @@ pgf_parser_init_state(PgfConcr* concr, PgfCId cat, size_t lin_idx,
                       GuPool* pool, GuPool* out_pool)
 {
 	PgfCncCat* cnccat =
-		gu_map_get(concr->cnccats, &cat, PgfCncCat*);
+		gu_map_get(concr->cnccats, cat, PgfCncCat*);
 	if (!cnccat)
 		return NULL;
 
@@ -2226,7 +2211,7 @@ pgf_parser_add_literal(PgfConcr *concr, PgfCId cat,
                        PgfLiteralCallback* callback)
 {
 	PgfCncCat* cnccat =
-		gu_map_get(concr->cnccats, &cat, PgfCncCat*);
+		gu_map_get(concr->cnccats, cat, PgfCncCat*);
 	if (cnccat == NULL)
 		return;
 
@@ -2281,7 +2266,7 @@ pgf_morpho_iter(GuMapItor* fn, const void* key, void* value, GuExn* err)
 						PgfToken tok1 = symks->token;
 						PgfToken tok2 = gu_seq_get(clo->tokens, PgfToken, pos++);
 
-						if (!gu_string_eq(tok1, tok2))
+						if (strcmp(tok1, tok2) != 0)
 							goto cont;
 					}
 					default:
@@ -2320,7 +2305,7 @@ pgf_lookup_morpho(PgfConcr *concr, PgfLexer *lexer,
 	}
 
 	PgfProductionIdx* lexicon_idx =
-		gu_map_get(concr->leftcorner_tok_idx, &tok, PgfProductionIdx*);
+		gu_map_get(concr->leftcorner_tok_idx, tok, PgfProductionIdx*);
 	if (lexicon_idx == NULL) {
 		gu_pool_free(tmp_pool);
 		return;
@@ -2374,10 +2359,10 @@ pgf_fullform_iter(GuMapItor* fn, const void* key, void* value, GuExn* err)
 			// create a new production index with keys that 
 			// are multiword units
 			PgfProductionIdx* lexicon_idx =
-				gu_map_get(st->new_idx, &tokens, PgfProductionIdx*);
+				gu_map_get(st->new_idx, tokens, PgfProductionIdx*);
 			if (lexicon_idx == NULL) {
 				lexicon_idx = gu_map_type_new(PgfProductionIdx, st->pool);
-				gu_map_put(st->new_idx, &tokens, PgfProductionIdx*, lexicon_idx);
+				gu_map_put(st->new_idx, tokens, PgfProductionIdx*, lexicon_idx);
 			}
 
 			PgfProductionBuf* prods =
@@ -2443,7 +2428,7 @@ pgf_fullform_lexicon(PgfConcr *concr, GuPool* pool)
 GuString
 pgf_fullform_get_string(PgfFullFormEntry* entry)
 {
-	return *((GuString*) entry->key);
+	return (GuString) entry->key;
 }
 
 void
@@ -2462,10 +2447,10 @@ pgf_parser_index_token(PgfConcr* concr,
                        GuPool *pool)
 {
 	PgfProductionIdx* set =
-		gu_map_get(concr->leftcorner_tok_idx, &tok, PgfProductionIdx*);
+		gu_map_get(concr->leftcorner_tok_idx, tok, PgfProductionIdx*);
 	if (set == NULL) {
 		set = gu_map_type_new(PgfProductionIdx, pool);
-		gu_map_put(concr->leftcorner_tok_idx, &tok, PgfProductionIdx*, set);
+		gu_map_put(concr->leftcorner_tok_idx, tok, PgfProductionIdx*, set);
 	}
 
 	PgfCFCat cfc = {ccat, lin_idx};
@@ -2527,6 +2512,7 @@ pgf_parser_index_symbol(PgfConcr* concr, PgfSymbol sym,
 	case PGF_SYMBOL_CAT:
 	case PGF_SYMBOL_LIT:
 	case PGF_SYMBOL_NE:
+	case PGF_SYMBOL_BIND:
 	case PGF_SYMBOL_VAR:
 		// Nothing to be done here
 		break;

src/runtime/c/pgf/parseval.c

@@ -111,7 +111,7 @@ pgf_metrics_lzn_end_phrase2(PgfLinFuncs** funcs, PgfCId cat, int fid, int lin_id
 			
 			if (phrase->start == start &&
 				phrase->end   == end &&
-				gu_string_eq(phrase->cat, cat) &&
+				strcmp(phrase->cat, cat) == 0 &&
 				phrase->lin_idx == lin_idx) {
 				state->matches++;
 				break;

src/runtime/c/pgf/pgf.c

@@ -49,30 +49,28 @@ pgf_load_meta_child_probs(PgfPGF* pgf, const char* fpath,
 	GuPool* tmp_pool = gu_new_pool();
 	
 	for (;;) {
-		char cat1_s[21];
+		char cat1[21];
-		char cat2_s[21];
+		char cat2[21];
 		prob_t prob;
 
-		if (fscanf(fp, "%20s\t%20s\t%f", cat1_s, cat2_s, &prob) < 3)
+		if (fscanf(fp, "%20s\t%20s\t%f", cat1, cat2, &prob) < 3)
 			break;
 
 		prob = - log(prob);
 
-		GuString cat1 = gu_str_string(cat1_s, tmp_pool);
 		PgfAbsCat* abscat1 =
-			gu_map_get(pgf->abstract.cats, &cat1, PgfAbsCat*);
+			gu_map_get(pgf->abstract.cats, cat1, PgfAbsCat*);
 		if (abscat1 == NULL) {
 			gu_raise(err, PgfExn);
 			goto close;
 		}
 
-		if (strcmp(cat2_s, "*") == 0) {
+		if (strcmp(cat2, "*") == 0) {
 			abscat1->meta_prob = prob;
-		} else if (strcmp(cat2_s, "_") == 0) {
+		} else if (strcmp(cat2, "_") == 0) {
 			abscat1->meta_token_prob = prob;
 		} else {
-			GuString cat2 = gu_str_string(cat2_s, tmp_pool);
+			PgfAbsCat* abscat2 = gu_map_get(pgf->abstract.cats, cat2, PgfAbsCat*);
-			PgfAbsCat* abscat2 = gu_map_get(pgf->abstract.cats, &cat2, PgfAbsCat*);
 			if (abscat2 == NULL) {
 				gu_raise(err, PgfExn);
 				goto close;
@@ -107,7 +105,7 @@ pgf_iter_languages(PgfPGF* pgf, GuMapItor* fn, GuExn* err)
 PgfConcr*
 pgf_get_language(PgfPGF* pgf, PgfCId lang)
 {
-	return gu_map_get(pgf->concretes, &lang, PgfConcr*);
+	return gu_map_get(pgf->concretes, lang, PgfConcr*);
 }
 
 GuString
@@ -123,16 +121,13 @@ pgf_iter_categories(PgfPGF* pgf, GuMapItor* fn, GuExn* err)
 }
 
 PgfCId
-pgf_start_cat(PgfPGF* pgf, GuPool* pool)
+pgf_start_cat(PgfPGF* pgf)
 {
-	GuPool* tmp_pool = gu_local_pool();
-
-	GuString s = gu_str_string("startcat", tmp_pool);
 	PgfLiteral lit =
-		gu_map_get(pgf->abstract.aflags, &s, PgfLiteral);
+		gu_map_get(pgf->abstract.aflags, "startcat", PgfLiteral);
 
 	if (gu_variant_is_null(lit))
-		return gu_str_string("S", pool);
+		return "S";
 
 	GuVariantInfo i = gu_variant_open(lit);
 	switch (i.tag) {
@@ -142,20 +137,17 @@ pgf_start_cat(PgfPGF* pgf, GuPool* pool)
 	}
 	}
 
-	return gu_str_string("S", pool);
+	return "S";
 }
 
 GuString
 pgf_language_code(PgfConcr* concr)
 {
-	GuPool* tmp_pool = gu_local_pool();
-
-	GuString s = gu_str_string("language", tmp_pool);
 	PgfLiteral lit =
-		gu_map_get(concr->cflags, &s, PgfLiteral);
+		gu_map_get(concr->cflags, "language", PgfLiteral);
 
 	if (gu_variant_is_null(lit))
-		return gu_empty_string;
+		return "";
 
 	GuVariantInfo i = gu_variant_open(lit);
 	switch (i.tag) {
@@ -165,7 +157,7 @@ pgf_language_code(PgfConcr* concr)
 	}
 	}
 
-	return gu_empty_string;
+	return "";
 }
 
 void
@@ -188,8 +180,8 @@ pgf_filter_by_cat(GuMapItor* fn, const void* key, void* value, GuExn* err)
 	PgfFunByCatIter* clo = (PgfFunByCatIter*) fn;
 	PgfAbsFun* absfun = *((PgfAbsFun**) value);
 	
-	if (gu_string_eq(absfun->type->cid, clo->catname)) {
+	if (strcmp(absfun->type->cid, clo->catname) == 0) {
-		clo->client_fn->fn(clo->client_fn, &absfun->name, NULL, err);
+		clo->client_fn->fn(clo->client_fn, absfun->name, NULL, err);
 	}
 }
 
@@ -205,10 +197,10 @@ PgfType*
 pgf_function_type(PgfPGF* pgf, PgfCId funname) 
 {
 	PgfAbsFun* absfun =
-		gu_map_get(pgf->abstract.funs, &funname, PgfAbsFun*);
+		gu_map_get(pgf->abstract.funs, funname, PgfAbsFun*);
 	if (absfun == NULL)
 		return NULL;
-		
+
 	return absfun->type;
 }
 
@@ -216,8 +208,8 @@ GuString
 pgf_print_name(PgfConcr* concr, PgfCId id)
 {
 	PgfCId name =
-		gu_map_get(concr->printnames, &id, PgfCId);
+		gu_map_get(concr->printnames, id, PgfCId);
-	if (gu_string_eq(name, gu_empty_string))
+	if (*name == 0)
 		name = id;
 	return name;
 }
@@ -226,7 +218,7 @@ void
 pgf_linearize(PgfConcr* concr, PgfExpr expr, GuOut* out, GuExn* err)
 {
 	GuPool* tmp_pool = gu_local_pool();
-	
+
 	GuEnum* cts = 
 		pgf_lzr_concretize(concr, expr, tmp_pool);
 	PgfCncTree ctree = gu_next(cts, PgfCncTree, tmp_pool);

src/runtime/c/pgf/pgf.h

@@ -102,7 +102,7 @@ void
 pgf_iter_categories(PgfPGF* pgf, GuMapItor* fn, GuExn* err);
 
 PgfCId
-pgf_start_cat(PgfPGF* pgf, GuPool* pool);
+pgf_start_cat(PgfPGF* pgf);
 
 void
 pgf_iter_functions(PgfPGF* pgf, GuMapItor* fn, GuExn* err);

src/runtime/c/pgf/reader.c

@@ -13,7 +13,7 @@
 #include <gu/exn.h>
 #include <gu/utf8.h>
 #include <math.h>
-#include <stdio.h>
+#include <stdlib.h>
 
 //
 // PgfReader
@@ -116,11 +116,21 @@ pgf_read_literal(PgfReader* rdr)
 	uint8_t tag = pgf_read_tag(rdr);
 	switch (tag) {
 	case PGF_LITERAL_STR: {
+		GuLength len = pgf_read_len(rdr);
+		uint8_t* buf = alloca(len*6+1);
+		uint8_t* p   = buf;
+		for (size_t i = 0; i < len; i++) {
+			gu_in_utf8_buf(&p, rdr->in, rdr->err);
+			gu_return_on_exn(rdr->err, gu_null_variant);
+		}
+		*p++ = 0;
+
 		PgfLiteralStr *lit_str =
-			gu_new_variant(PGF_LITERAL_STR,
+			gu_new_flex_variant(PGF_LITERAL_STR,
-						   PgfLiteralStr,
+						        PgfLiteralStr,
-						   &lit, rdr->opool);
+						        val, p-buf,
-		lit_str->val = pgf_read_string(rdr);
+						        &lit, rdr->opool);
+		strcpy((char*) lit_str->val, (char*) buf);
 		break;
 	}
 	case PGF_LITERAL_INT: {
@@ -160,7 +170,7 @@ pgf_read_flags(PgfReader* rdr)
 		PgfLiteral value = pgf_read_literal(rdr);
 		gu_return_on_exn(rdr->err, NULL);
 		
-		gu_map_put(flags, &name, PgfLiteral, value);
+		gu_map_put(flags, name, PgfLiteral, value);
 	}
 
 	return flags;
@@ -224,11 +234,16 @@ pgf_read_expr_(PgfReader* rdr)
 		break;
 	}
 	case PGF_EXPR_FUN: {
+		size_t len = pgf_read_len(rdr);
+
 		PgfExprFun *efun =
-			gu_new_variant(PGF_EXPR_FUN,
+			gu_new_flex_variant(PGF_EXPR_FUN,
-						   PgfExprFun,
+						        PgfExprFun,
-						   &expr, rdr->opool);
+						        fun, len+1,
-		efun->fun = pgf_read_cid(rdr, rdr->opool);
+						        &expr, rdr->opool);
+		gu_in_bytes(rdr->in, (uint8_t*)efun->fun, len, rdr->err);
+		efun->fun[len] = 0;
+		
 		gu_return_on_exn(rdr->err, gu_null_variant);
 		break;
 	}
@@ -403,7 +418,17 @@ pgf_read_absfun(PgfReader* rdr)
 {
 	PgfAbsFun* absfun = gu_new(PgfAbsFun, rdr->opool);
 
-	absfun->name = pgf_read_cid(rdr, rdr->opool);
+	size_t len = pgf_read_len(rdr);
+
+	PgfExprFun *efun =
+		gu_new_flex_variant(PGF_EXPR_FUN,
+							PgfExprFun,
+							fun, len+1,
+							&absfun->ep.expr, rdr->opool);
+	gu_in_bytes(rdr->in, (uint8_t*)efun->fun, len, rdr->err);
+	efun->fun[len] = 0;
+	absfun->name = efun->fun;
+
 	gu_return_on_exn(rdr->err, NULL);
 
 	absfun->type = pgf_read_type_(rdr);
@@ -449,12 +474,6 @@ pgf_read_absfun(PgfReader* rdr)
 
 	absfun->ep.prob = - log(gu_in_f64be(rdr->in, rdr->err));
 
-	PgfExprFun* expr_fun =
-		gu_new_variant(PGF_EXPR_FUN,
-					   PgfExprFun,
-					   &absfun->ep.expr, rdr->opool);
-	expr_fun->fun = absfun->name;
-
 	return absfun;
 }
 					    
@@ -474,7 +493,7 @@ pgf_read_absfuns(PgfReader* rdr)
 		PgfAbsFun* absfun = pgf_read_absfun(rdr);
 		gu_return_on_exn(rdr->err, NULL);
 		
-		gu_map_put(absfuns, &absfun->name, PgfAbsFun*, absfun);
+		gu_map_put(absfuns, absfun->name, PgfAbsFun*, absfun);
 	}
 
 	return absfuns;
@@ -514,7 +533,8 @@ pgf_read_abscat(PgfReader* rdr, PgfAbstr* abstr, PgfCIdMap* abscats)
 		gu_return_on_exn(rdr->err, NULL);
 		
 		PgfAbsFun* absfun =
-			gu_map_get(abstr->funs, &name, PgfAbsFun*);
+			gu_map_get(abstr->funs, name, PgfAbsFun*);
+		assert(absfun != NULL);
 		gu_buf_push(functions, PgfAbsFun*, absfun);
 	}
 
@@ -539,7 +559,7 @@ pgf_read_abscats(PgfReader* rdr, PgfAbstr* abstr)
 		PgfAbsCat* abscat = pgf_read_abscat(rdr, abstr, abscats);
 		gu_return_on_exn(rdr->err, NULL);
 
-		gu_map_put(abscats, &abscat->name, PgfAbsCat*, abscat);
+		gu_map_put(abscats, abscat->name, PgfAbsCat*, abscat);
 	}
 
 	return abscats;
@@ -567,7 +587,7 @@ pgf_read_printnames(PgfReader* rdr)
 	GuMapType* map_type = (GuMapType*)
 		GU_TYPE_LIT(GuStringMap, _,
 			 		gu_type(GuString),
-					&gu_empty_string);
+					&"");
 	PgfCIdMap* printnames = gu_map_type_make(map_type, rdr->opool);
 
 	size_t len = pgf_read_len(rdr);
@@ -580,7 +600,7 @@ pgf_read_printnames(PgfReader* rdr)
 		GuString printname = pgf_read_string(rdr);
 		gu_return_on_exn(rdr->err, NULL);
 
-		gu_map_put(printnames, &name, GuString, printname);
+		gu_map_put(printnames, name, GuString, printname);
 	}
 
 	return printnames;
@@ -654,12 +674,21 @@ pgf_read_symbol(PgfReader* rdr)
 		break;
 	}
 	case PGF_SYMBOL_KS: {
+		GuLength len = pgf_read_len(rdr);
+		uint8_t* buf = alloca(len*6+1);
+		uint8_t* p   = buf;
+		for (size_t i = 0; i < len; i++) {
+			gu_in_utf8_buf(&p, rdr->in, rdr->err);
+			gu_return_on_exn(rdr->err, gu_null_variant);
+		}
+		*p++ = 0;
+
 		PgfSymbolKS *sym_ks =
-			gu_new_variant(PGF_SYMBOL_KS,
+			gu_new_flex_variant(PGF_SYMBOL_KS,
-						   PgfSymbolKS,
+						        PgfSymbolKS,
-						   &sym, rdr->opool);
+						        token, p-buf,
-		sym_ks->token = pgf_read_string(rdr);
+						        &sym, rdr->opool);
-		gu_return_on_exn(rdr->err, gu_null_variant);
+		strcpy((char*) sym_ks->token, (char*) buf);
 		break;
 	}
 	case PGF_SYMBOL_KP: {
@@ -747,7 +776,7 @@ pgf_read_cncfun(PgfReader* rdr, PgfAbstr* abstr, PgfConcr* concr, int funid)
 	gu_return_on_exn(rdr->err, NULL);
 
 	PgfAbsFun* absfun =
-		gu_map_get(abstr->funs, &name, PgfAbsFun*);
+		gu_map_get(abstr->funs, name, PgfAbsFun*);
 
 	PgfCncFun* cncfun = gu_new_flex(rdr->opool, PgfCncFun, lins, len);
 	cncfun->absfun = absfun;
@@ -956,7 +985,7 @@ pgf_read_cnccat(PgfReader* rdr, PgfAbstr* abstr, PgfConcr* concr, PgfCId name)
 		gu_malloc(rdr->opool, sizeof(PgfCncCat)+n_lins*sizeof(GuString));
 
 	cnccat->abscat = 
-		gu_map_get(abstr->cats, &name, PgfAbsCat*);
+		gu_map_get(abstr->cats, name, PgfAbsCat*);
 	gu_assert(cnccat->abscat != NULL);
 
 	int len = last + 1 - first;
@@ -1011,7 +1040,7 @@ pgf_read_cnccats(PgfReader* rdr, PgfAbstr* abstr, PgfConcr* concr)
 			pgf_read_cnccat(rdr, abstr, concr, name);
 		gu_return_on_exn(rdr->err, NULL);
 		
-		gu_map_put(cnccats, &name, PgfCncCat*, cnccat);
+		gu_map_put(cnccats, name, PgfCncCat*, cnccat);
 	}
 
 	return cnccats;
@@ -1100,7 +1129,7 @@ pgf_read_concrete(PgfReader* rdr, PgfAbstr* abstr)
 		pgf_read_cid(rdr, rdr->opool);
 	gu_return_on_exn(rdr->err, NULL);
 
-	concr->cflags = 
+	concr->cflags =
 		pgf_read_flags(rdr);
 	gu_return_on_exn(rdr->err, NULL);
 	
@@ -1150,7 +1179,7 @@ pgf_read_concretes(PgfReader* rdr, PgfAbstr* abstr)
 		PgfConcr* concr = pgf_read_concrete(rdr, abstr);
 		gu_return_on_exn(rdr->err, NULL);
 		
-		gu_map_put(concretes, &concr->name, PgfConcr*, concr);
+		gu_map_put(concretes, concr->name, PgfConcr*, concr);
 	}
 
 	return concretes;

src/runtime/c/pgf/reasoner.c

@@ -230,14 +230,14 @@ pgf_reasoner_try_first(PgfReasoner* rs, PgfExprState* parent, PgfAbsFun* absfun)
 {
 	PgfCId cat = absfun->type->cid;
 
-	PgfAnswers* answers = gu_map_get(rs->table, &cat, PgfAnswers*);
+	PgfAnswers* answers = gu_map_get(rs->table, cat, PgfAnswers*);
 	if (answers == NULL) {
 		answers = gu_new(PgfAnswers, rs->tmp_pool);
 		answers->parents = gu_new_buf(PgfExprState*, rs->tmp_pool);
 		answers->exprs   = gu_new_buf(PgfExprProb*, rs->tmp_pool);
 		answers->outside_prob = parent->base.prob;
 
-		gu_map_put(rs->table, &cat, PgfAnswers*, answers);
+		gu_map_put(rs->table, cat, PgfAnswers*, answers);
 	}
 
 	gu_buf_push(answers->parents, PgfExprState*, parent);
@@ -397,9 +397,9 @@ pgf_generate_all(PgfPGF* pgf, PgfCId cat, GuPool* pool)
 	answers->parents = gu_new_buf(PgfExprState*, rs->tmp_pool);
 	answers->exprs   = rs->exprs;
 	answers->outside_prob = 0;
-	gu_map_put(rs->table, &cat, PgfAnswers*, answers);
+	gu_map_put(rs->table, cat, PgfAnswers*, answers);
 
-	PgfAbsCat* abscat = gu_map_get(rs->abstract->cats, &cat, PgfAbsCat*);
+	PgfAbsCat* abscat = gu_map_get(rs->abstract->cats, cat, PgfAbsCat*);
 	if (abscat != NULL) {
 		((PgfPredicate) abscat->predicate)(rs, NULL);
 	}

src/runtime/c/utils/pgf-parse.c

@@ -28,8 +28,8 @@ int main(int argc, char* argv[]) {
     goto fail;
   }
   char* filename = argv[1];
-  GuString cat = gu_str_string(argv[2], pool);
+  GuString cat = argv[2];
-  GuString lang = gu_str_string(argv[3], pool);
+  GuString lang = argv[3];
 
   double heuristics = 0.95;
   if (argc == 5) {
@@ -61,7 +61,7 @@ int main(int argc, char* argv[]) {
   }
 
   /* // Register a callback for the literal category Symbol */
-  /* pgf_parser_add_literal(from_concr, gu_str_string("Symb", pool), */
+  /* pgf_parser_add_literal(from_concr, "Symb", */
   /*                        &pgf_nerc_literal_callback); */
 
   clock_t end = clock();
@@ -110,7 +110,7 @@ int main(int argc, char* argv[]) {
 
     clock_t start = clock();
 
-    GuIn *in = gu_string_in(gu_str_string(line, ppool), ppool);
+    GuIn *in = gu_string_in(line, ppool);
     PgfLexer *lexer = pgf_new_simple_lexer(in, ppool);
     GuEnum* result = pgf_parse_with_heuristics(concr, cat, lexer, heuristics, ppool, ppool);
 

src/runtime/c/utils/pgf-service.c

@@ -200,8 +200,8 @@ int main ()
 		goto fail;
 	}
 
-	GuString cat = gu_str_string("Phr", pool);
+	GuString cat = "Phr";
-	GuString from_lang = gu_str_string("ParseEng", pool);
+	GuString from_lang = "ParseEng";
 	PgfConcr* from_concr =
 		pgf_get_language(pgf, from_lang);
 	if (!from_concr) {
@@ -210,7 +210,7 @@ int main ()
 	}
 
 	// Register a callback for the literal category Symbol
-	pgf_parser_add_literal(from_concr, gu_str_string("Symb", pool),
+	pgf_parser_add_literal(from_concr, "Symb",
 	                       &pgf_nerc_literal_callback);
 
     while (FCGI_Accept() >= 0) {
@@ -233,7 +233,7 @@ int main ()
 
 			PgfConcr* to_concr = NULL;
 			if (strlen(to_lang_buf) > 0) {
-				GuString to_lang = gu_str_string(to_lang_buf, ppool);
+				GuString to_lang = to_lang_buf;
 				to_concr =
 					pgf_get_language(pgf, to_lang);
 				if (!to_concr) {
@@ -248,7 +248,7 @@ int main ()
 			sentence[len+1] = '\0';
 		
 			GuReader *rdr =
-				gu_string_reader(gu_str_string(sentence, ppool), ppool);
+				gu_string_reader(sentence, ppool);
 			PgfLexer *lexer =
 				pgf_new_simple_lexer(rdr, ppool);
 

src/runtime/c/utils/pgf-translate.c

@@ -53,10 +53,10 @@ int main(int argc, char* argv[]) {
 	}
 	char* filename = argv[1];
 
-	GuString cat = gu_str_string(argv[2], pool);
+	GuString cat = argv[2];
 
-	GuString from_lang = gu_str_string(argv[3], pool);
+	GuString from_lang = argv[3];
-	GuString to_lang = gu_str_string(argv[4], pool);
+	GuString to_lang = argv[4];
 	
 	// Create an exception frame that catches all errors.
 	GuExn* err = gu_new_exn(NULL, gu_kind(type), pool);
@@ -91,7 +91,7 @@ int main(int argc, char* argv[]) {
 	}
 	
 	// Register a callback for the literal category Symbol
-	pgf_parser_add_literal(from_concr, gu_str_string("Symb", pool),
+	pgf_parser_add_literal(from_concr, "Symb",
 	                       &pgf_nerc_literal_callback);
 
 	// Create an output stream for stdout
@@ -154,7 +154,7 @@ int main(int argc, char* argv[]) {
 		ppool = gu_new_pool();
 
 		GuIn *in =
-			gu_string_in(gu_str_string(line, ppool), ppool);
+			gu_string_in(line, ppool);
 		PgfLexer *lexer =
 			pgf_new_simple_lexer(in, ppool);
 
@@ -166,7 +166,7 @@ int main(int argc, char* argv[]) {
 			PgfToken tok =
 				pgf_lexer_current_token(lexer);
 
-			if (gu_string_eq(tok, gu_empty_string))
+			if (*tok == 0)
 				gu_puts("Couldn't begin parsing", out, err);
 			else {
 				gu_puts("Unexpected token: \"", out, err);

src/runtime/java/jpgf.c

@@ -11,32 +11,13 @@
 
 static jstring
 gu2j_string(JNIEnv *env, GuString s) {
-	GuWord w = s.w_;
+	const char* utf8 = s;
-	uint8_t buf[sizeof(GuWord)];
+	size_t len = strlen(s);
-
-	uint8_t* utf8;
-	size_t len;
-	if (w & 1) {
-		len = (w & 0xff) >> 1;
-		gu_assert(len <= sizeof(GuWord));
-		size_t i = len;
-		while (i > 0) {
-			w >>= 8;
-			buf[--i] = w & 0xff;
-		}
-		utf8 = buf;
-	} else {
-		uint8_t* p = (void*) w;
-		len = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		utf8 = &p[1];
-	}
-
-	const uint8_t* src = utf8;
 
 	jchar* utf16 = alloca(len*sizeof(jchar));
 	jchar* dst   = utf16;
-	while (src-utf8 < len) {
+	while (s-utf8 < len) {
-		GuUCS ucs = gu_utf8_decode(&src);
+		GuUCS ucs = gu_utf8_decode((const uint8_t**) &s);
 		
 		if (ucs <= 0xFFFF) {
 			*dst++ = ucs;
@@ -52,10 +33,10 @@ gu2j_string(JNIEnv *env, GuString s) {
 
 static GuString
 j2gu_string(JNIEnv *env, jstring s, GuPool* pool) {
-	const char *str = (*env)->GetStringUTFChars(env, s, 0);
+	GuString str = (*env)->GetStringUTFChars(env, s, 0);
-	GuString s = gu_str_string(str, pool);
+	str = gu_string_copy(str, pool);
 	(*env)->ReleaseStringUTFChars(env, s, str);
-	return s;
+	return str;
 }
 
 static void*
@@ -223,10 +204,7 @@ Java_org_grammaticalframework_pgf_PGF_getAbstractName(JNIEnv* env, jobject self)
 JNIEXPORT jstring JNICALL
 Java_org_grammaticalframework_pgf_PGF_getStartCat(JNIEnv* env, jobject self)
 {
-	GuPool* tmp_pool = gu_local_pool();
+	return gu2j_string(env, pgf_start_cat(get_ref(env, self)));
-	jstring jname = gu2j_string(env, pgf_start_cat(get_ref(env, self), tmp_pool));
-	gu_pool_free(tmp_pool);
-	return jname;
 }
 
 typedef struct {
@@ -313,7 +291,7 @@ Java_org_grammaticalframework_pgf_Parser_parse
 		PgfToken tok =
 			pgf_lexer_current_token(lexer);
 
-		if (gu_string_eq(tok, gu_empty_string))
+		if (*tok == 0)
 			throw_string_exception(env, "org/grammaticalframework/pgf/PGFError", "The sentence cannot be parsed");
 		else
 			throw_jstring_exception(env, "org/grammaticalframework/pgf/ParseError", gu2j_string(env, tok));

src/runtime/python/pypgf.c

@@ -12,31 +12,6 @@ static PyObject* PGFError;
 
 static PyObject* ParseError;
 
-static PyObject*
-gu2py_string(GuString s) {
-	GuWord w = s.w_;
-	uint8_t buf[sizeof(GuWord)];
-
-	char* src;
-	size_t len;
-	if (w & 1) {
-		len = (w & 0xff) >> 1;
-		gu_assert(len <= sizeof(GuWord));
-		size_t i = len;
-		while (i > 0) {
-			w >>= 8;
-			buf[--i] = w & 0xff;
-		}
-		src = (char*) buf;
-	} else {
-		uint8_t* p = (void*) w;
-		len = (p[0] == 0) ? ((size_t*) p)[-1] : p[0];
-		src = (char*) &p[1];
-	}
-
-	return PyString_FromStringAndSize(src, len);
-}
-
 typedef struct {
     PyObject_HEAD
     GuPool* pool;
@@ -129,7 +104,7 @@ Expr_repr(ExprObject *self)
 	pgf_print_expr(self->expr, NULL, 0, out, err);
 
 	GuString str = gu_string_buf_freeze(sbuf, tmp_pool);
-	PyObject* pystr = gu2py_string(str);
+	PyObject* pystr = PyString_FromString(str);
 	
 	gu_pool_free(tmp_pool);
 	return pystr;
@@ -258,11 +233,13 @@ Expr_initLiteral(ExprObject *self, PyObject *lit)
 	e->lit = gu_null_variant;
 
 	if (PyString_Check(lit)) {
+		GuString s = PyString_AsString(lit);
 		PgfLiteralStr* slit =
-			gu_new_variant(PGF_LITERAL_STR,
+			gu_new_flex_variant(PGF_LITERAL_STR,
-			               PgfLiteralStr,
+			                    PgfLiteralStr,
-			               &e->lit, self->pool);
+			                    val, strlen(s)+1,
-		slit->val = gu_str_string(PyString_AsString(lit), self->pool);
+			                    &e->lit, self->pool);
+		strcpy(slit->val, s);
 	} else if (PyInt_Check(lit)) {
 		PgfLiteralInt* ilit =
 			gu_new_variant(PGF_LITERAL_INT,
@@ -293,10 +270,11 @@ Expr_initApp(ExprObject *self, const char* fname, PyObject *args)
 
 	self->pool = gu_new_pool();
 	PgfExprFun* e =
-		gu_new_variant(PGF_EXPR_FUN,
+		gu_new_flex_variant(PGF_EXPR_FUN,
-					   PgfExprFun,
+					        PgfExprFun,
-					   &self->expr, self->pool);
+					        fun, strlen(fname)+1,
-	e->fun = gu_str_string(fname, self->pool);
+					        &self->expr, self->pool);
+	strcpy(e->fun, fname);
 
 	for (Py_ssize_t i = 0; i < n_args; i++) {
 		PyObject* obj = PyList_GetItem(args, i);
@@ -345,7 +323,7 @@ Expr_unpack(ExprObject* self, PyObject *fargs)
 			PyObject* py_bindtype = 
 				(eabs->bind_type == PGF_BIND_TYPE_EXPLICIT) ? Py_True
 				                                            : Py_False;
-			PyObject* py_var = gu2py_string(eabs->id);
+			PyObject* py_var = PyString_FromString(eabs->id);
 			PyObject* res = 
 				Py_BuildValue("OOOO", py_bindtype, py_var, py_body, args);
 			Py_DECREF(py_var);
@@ -383,7 +361,7 @@ Expr_unpack(ExprObject* self, PyObject *fargs)
 			switch (i.tag) {
 			case PGF_LITERAL_STR: {
 				PgfLiteralStr* lstr = i.data;
-				return gu2py_string(lstr->val);
+				return PyString_FromString(lstr->val);
 			}
 			case PGF_LITERAL_INT: {
 				PgfLiteralInt* lint = i.data;
@@ -405,7 +383,7 @@ Expr_unpack(ExprObject* self, PyObject *fargs)
 		}
 		case PGF_EXPR_FUN: {
 			PgfExprFun* efun = i.data;
-			PyObject* fun = gu2py_string(efun->fun);
+			PyObject* fun = PyString_FromString(efun->fun);
 			PyObject* res = Py_BuildValue("OO", fun, args);
 			Py_DECREF(fun);
 			Py_DECREF(args);
@@ -482,7 +460,7 @@ redo:;
 			}
 			case PGF_LITERAL_STR: {
 				PgfLiteralStr* lstr = i.data;
-				return gu2py_string(lstr->val);
+				return PyString_FromString(lstr->val);
 			}
 			}
 		}
@@ -497,7 +475,7 @@ redo:;
 	case PGF_EXPR_FUN: {
 		PgfExprFun* efun = i.data;
 		if (strcmp(name, "name") == 0) {
-			return gu2py_string(efun->fun);
+			return PyString_FromString(efun->fun);
 		}
 		break;
 	}
@@ -604,7 +582,7 @@ Type_init(TypeObject *self, PyObject *args, PyObject *kwds)
 
 		if (obj->ob_type == &pgf_TypeType) {
 			py_bindtype = Py_True;
-			cid = gu_str_string("_", self->pool);
+			cid = "_";
 			py_type = obj;
 		} else {
 			if (!PyTuple_Check(obj) ||
@@ -624,7 +602,7 @@ Type_init(TypeObject *self, PyObject *args, PyObject *kwds)
 				PyErr_SetString(PyExc_TypeError, "the arguments in the first list must be triples of (boolean,string,pgf.Type)");
 				return -1;
 			}
-			cid = gu_str_string(PyString_AsString(py_var), self->pool);
+			cid = gu_string_copy(PyString_AsString(py_var), self->pool);
 
 			py_type = PyTuple_GetItem(obj, 2);
 			if (py_type->ob_type != &pgf_TypeType) {
@@ -644,7 +622,7 @@ Type_init(TypeObject *self, PyObject *args, PyObject *kwds)
 		Py_INCREF(py_type);
 	}
 
-	self->type->cid = gu_str_string(catname_s, self->pool);
+	self->type->cid = gu_string_copy(catname_s, self->pool);
 
 	self->type->n_exprs = n_exprs;
 	for (Py_ssize_t i = 0; i < n_exprs; i++) {
@@ -675,7 +653,7 @@ Type_repr(TypeObject *self)
 	pgf_print_type(self->type, NULL, 0, out, err);
 
 	GuString str = gu_string_buf_freeze(sbuf, tmp_pool);
-	PyObject* pystr = gu2py_string(str);
+	PyObject* pystr = PyString_FromString(str);
 	
 	gu_pool_free(tmp_pool);
 	return pystr;
@@ -713,7 +691,7 @@ Type_getHypos(TypeObject *self, void *closure)
 			(hypo->bind_type == PGF_BIND_TYPE_EXPLICIT) ? Py_True
 						  							    : Py_False;
 
-		PyObject* py_var = gu2py_string(hypo->cid);
+		PyObject* py_var = PyString_FromString(hypo->cid);
 		if (py_var == NULL)
 			goto fail;
 
@@ -752,7 +730,7 @@ fail:
 static PyObject*
 Type_getCat(TypeObject *self, void *closure)
 {
-	return gu2py_string(self->type->cid);
+	return PyString_FromString(self->type->cid);
 }
 
 static PyObject*
@@ -920,8 +898,8 @@ Iter_fetch_token(IterObject* self)
 	if (tp == NULL)
 		return NULL;
 
-	PyObject* py_tok = gu2py_string(tp->tok);
+	PyObject* py_tok = PyString_FromString(tp->tok);
-	PyObject* py_cat = gu2py_string(tp->cat);
+	PyObject* py_cat = PyString_FromString(tp->cat);
 	PyObject* res = Py_BuildValue("(f,O,O)", tp->prob, py_tok, py_cat);
 	Py_DECREF(py_tok);
 
@@ -1061,16 +1039,11 @@ Concr_init(ConcrObject *self, PyObject *args, PyObject *kwds)
 static PyObject*
 Concr_printName(ConcrObject* self, PyObject *args)
 {
-	const char *name_s;
+	GuString name;
-    if (!PyArg_ParseTuple(args, "s", &name_s))
+    if (!PyArg_ParseTuple(args, "s", &name))
         return NULL;
 
-	GuPool *tmp_pool = gu_local_pool();
+	return PyString_FromString(pgf_print_name(self->concr, name));
-    GuString name = gu_str_string(name_s, tmp_pool);
-    PyObject* pyname = gu2py_string(pgf_print_name(self->concr, name));
-	gu_pool_free(tmp_pool);
-
-	return pyname;
 }
 
 typedef struct {
@@ -1085,7 +1058,7 @@ static PgfToken
 pypgf_python_lexer_read_token(PgfLexer *base, GuExn* err)
 {
 	PgfPythonLexer* lexer = (PgfPythonLexer*) base;
-	lexer->base.tok = gu_empty_string;
+	lexer->base.tok = "";
 
 	PyObject* item = PyIter_Next(lexer->pylexer);
 	if (item == NULL)
@@ -1098,7 +1071,7 @@ pypgf_python_lexer_read_token(PgfLexer *base, GuExn* err)
 		if (str == NULL)
 			gu_raise(err, PyPgfLexerExn);
 		else
-			lexer->base.tok = gu_str_string(str, lexer->pool);
+			lexer->base.tok = gu_string_copy(str, lexer->pool);
 	}
 
 	return lexer->base.tok;
@@ -1109,7 +1082,7 @@ pypgf_new_python_lexer(PyObject* pylexer, GuPool* pool)
 {
 	PgfPythonLexer* lexer = gu_new(PgfPythonLexer, pool);
 	lexer->base.read_token = pypgf_python_lexer_read_token;
-	lexer->base.tok = gu_empty_string;
+	lexer->base.tok = "";
 	lexer->pylexer = pylexer;
 	lexer->pool = pool;
 	return ((PgfLexer*) lexer);
@@ -1146,11 +1119,11 @@ Concr_parse(ConcrObject* self, PyObject *args, PyObject *keywds)
 	int len;
 	const uint8_t *buf = NULL;
 	PyObject* py_lexer = NULL;
-	const char *catname_s = NULL;
+	PgfCId catname = pgf_start_cat(self->grammar->pgf);
 	int max_count = -1;
 	double heuristics = -1;
     if (!PyArg_ParseTupleAndKeywords(args, keywds, "|s#Osid", kwlist,
-                                     &buf, &len, &py_lexer, &catname_s, &max_count, &heuristics))
+                                     &buf, &len, &py_lexer, &catname, &max_count, &heuristics))
         return NULL;
 
     if ((buf == NULL && py_lexer == NULL) || 
@@ -1187,10 +1160,6 @@ Concr_parse(ConcrObject* self, PyObject *args, PyObject *keywds)
 	pyres->counter   = 0;
 	pyres->fetch     = Iter_fetch_expr;
 
-    GuString catname =
-		(catname_s == NULL) ? pgf_start_cat(self->grammar->pgf, pyres->pool)
-		                    : gu_str_string(catname_s, pyres->pool);
-
 	PgfLexer *lexer = NULL;
 	if (buf != NULL) {
 		GuIn* in = gu_data_in(buf, len, pyres->pool);
@@ -1208,10 +1177,10 @@ Concr_parse(ConcrObject* self, PyObject *args, PyObject *keywds)
 		PgfToken tok =
 			pgf_lexer_current_token(lexer);
 
-		if (gu_string_eq(tok, gu_empty_string))
+		if (*tok == 0)
 			PyErr_SetString(PGFError, "The sentence cannot be parsed");
 		else {
-			PyObject* py_tok = gu2py_string(tok);
+			PyObject* py_tok = PyString_FromString(tok);
 			PyObject_SetAttrString(ParseError, "token", py_tok);
 			PyErr_Format(ParseError, "Unexpected token: \"%s\"", 
 										PyString_AsString(py_tok));
@@ -1236,12 +1205,12 @@ Concr_complete(ConcrObject* self, PyObject *args, PyObject *keywds)
 	int len;
 	const uint8_t *buf = NULL;
 	PyObject* py_lexer = NULL;
-	const char *catname_s = NULL;
+	GuString catname = pgf_start_cat(self->grammar->pgf);
-	const char *prefix_s = NULL;
+	GuString prefix = "";
 	int max_count = -1;
     if (!PyArg_ParseTupleAndKeywords(args, keywds, "|s#Ossi", kwlist,
-                                     &buf, &len, &py_lexer, &catname_s,
+                                     &buf, &len, &py_lexer, &catname,
-                                     &prefix_s, &max_count))
+                                     &prefix, &max_count))
         return NULL;
 
     if ((buf == NULL && py_lexer == NULL) || 
@@ -1276,14 +1245,6 @@ Concr_complete(ConcrObject* self, PyObject *args, PyObject *keywds)
 
 	GuPool *tmp_pool = gu_local_pool();
 
-    GuString catname =
-		(catname_s == NULL) ? pgf_start_cat(self->grammar->pgf, tmp_pool)
-		                    : gu_str_string(catname_s, tmp_pool);
-
-    GuString prefix =
-		(prefix_s == NULL) ? gu_empty_string
-		                   : gu_str_string(prefix_s, pyres->pool);
-
 	PgfLexer *lexer = NULL;
 	if (buf != NULL) {
 		GuIn* in = gu_data_in(buf, len, tmp_pool);
@@ -1303,10 +1264,10 @@ Concr_complete(ConcrObject* self, PyObject *args, PyObject *keywds)
 		PgfToken tok =
 			pgf_lexer_current_token(lexer);
 
-		if (gu_string_eq(tok, gu_empty_string))
+		if (*tok == 0)
 			PyErr_SetString(PGFError, "The sentence cannot be parsed");
 		else {
-			PyObject* py_tok = gu2py_string(tok);
+			PyObject* py_tok = PyString_FromString(tok);
 			PyObject_SetAttrString(ParseError, "token", py_tok);
 			PyErr_Format(ParseError, "Unexpected token: \"%s\"", 
 										PyString_AsString(py_tok));
@@ -1323,14 +1284,12 @@ Concr_complete(ConcrObject* self, PyObject *args, PyObject *keywds)
 static PyObject*
 Concr_parseval(ConcrObject* self, PyObject *args) {
 	ExprObject* pyexpr = NULL;
-	const char* s_cat = NULL;
+	PgfCId cat = "";
-	if (!PyArg_ParseTuple(args, "O!s", &pgf_ExprType, &pyexpr, &s_cat))
+	if (!PyArg_ParseTuple(args, "O!s", &pgf_ExprType, &pyexpr, &cat))
         return NULL;
         
     GuPool* tmp_pool = gu_local_pool();
 
-    PgfCId cat = gu_str_string(s_cat, tmp_pool);
-
 	double precision = 0;
 	double recall = 0;
 	double exact = 0;
@@ -1387,7 +1346,7 @@ Concr_linearize(ConcrObject* self, PyObject *args)
 	}
 
 	GuString str = gu_string_buf_freeze(sbuf, tmp_pool);
-	PyObject* pystr = gu2py_string(str);
+	PyObject* pystr = PyString_FromString(str);
 	
 	gu_pool_free(tmp_pool);
 	return pystr;
@@ -1526,7 +1485,7 @@ pgf_bracket_lzn_symbol_token(PgfLinFuncs** funcs, PgfToken tok)
 {
 	PgfBracketLznState* state = gu_container(funcs, PgfBracketLznState, funcs);
 
-	PyObject* str = gu2py_string(tok);
+	PyObject* str = PyString_FromString(tok);
 	PyList_Append(state->list, str);
 	Py_DECREF(str);
 }
@@ -1540,7 +1499,7 @@ pgf_bracket_lzn_expr_literal(PgfLinFuncs** funcs, PgfLiteral lit)
     switch (i.tag) {
     case PGF_LITERAL_STR: {
         PgfLiteralStr* lstr = i.data;
-        PyObject* str = gu2py_string(lstr->val);
+        PyObject* str = PyString_FromString(lstr->val);
 		PyList_Append(state->list, str);
 		Py_DECREF(str);
 		break;
@@ -1584,10 +1543,10 @@ pgf_bracket_lzn_end_phrase(PgfLinFuncs** funcs, PgfCId cat, int fid, int lindex,
 		BracketObject* bracket = (BracketObject *)
 			pgf_BracketType.tp_alloc(&pgf_BracketType, 0);
 		if (bracket != NULL) {
-			bracket->cat = gu2py_string(cat);
+			bracket->cat = PyString_FromString(cat);
 			bracket->fid = fid;
 			bracket->lindex = lindex;
-			bracket->fun = gu2py_string(fun);
+			bracket->fun = PyString_FromString(fun);
 			bracket->children = state->list;
 			PyList_Append(parent, (PyObject*) bracket);
 			Py_DECREF(bracket);
@@ -1652,13 +1611,13 @@ Concr_bracketedLinearize(ConcrObject* self, PyObject *args)
 static PyObject*
 Concr_getName(ConcrObject *self, void *closure)
 {
-    return gu2py_string(pgf_concrete_name(self->concr));
+    return PyString_FromString(pgf_concrete_name(self->concr));
 }
 
 static PyObject*
 Concr_getLanguageCode(ConcrObject *self, void *closure)
 {
-    return gu2py_string(pgf_language_code(self->concr));
+    return PyString_FromString(pgf_language_code(self->concr));
 }
 
 static PyObject*
@@ -1679,7 +1638,7 @@ Concr_graphvizParseTree(ConcrObject* self, PyObject *args) {
 	}
 
 	GuString str = gu_string_buf_freeze(sbuf, tmp_pool);
-	PyObject* pystr = gu2py_string(str);
+	PyObject* pystr = PyString_FromString(str);
 
 	gu_pool_free(tmp_pool);
 	return pystr;
@@ -1697,8 +1656,8 @@ pypgf_collect_morpho(PgfMorphoCallback* self,
 {
 	PyMorphoCallback* callback = (PyMorphoCallback*) self;
 
-	PyObject* py_lemma = gu2py_string(lemma);
+	PyObject* py_lemma = PyString_FromString(lemma);
-	PyObject* py_analysis = gu2py_string(analysis);
+	PyObject* py_analysis = PyString_FromString(analysis);
 	PyObject* res = 
 		Py_BuildValue("OOf", py_lemma, py_analysis, prob);
 
@@ -1780,7 +1739,7 @@ Iter_fetch_fullform(IterObject* self)
 	GuString tokens =
 		pgf_fullform_get_string(entry);
 		
-	py_tokens = gu2py_string(tokens);
+	py_tokens = PyString_FromString(tokens);
 	if (py_tokens == NULL)
 		goto done;
 
@@ -1936,7 +1895,7 @@ PGF_dealloc(PGFObject* self)
 static PyObject*
 PGF_getAbstractName(PGFObject *self, void *closure)
 {
-    return gu2py_string(pgf_abstract_name(self->pgf));
+    return PyString_FromString(pgf_abstract_name(self->pgf));
 }
 
 typedef struct {
@@ -1948,14 +1907,14 @@ typedef struct {
 static void
 pgf_collect_langs(GuMapItor* fn, const void* key, void* value, GuExn* err)
 {
-	PgfCId name = *((PgfCId*) key);
+	PgfCId name = (PgfCId) key;
     PgfConcr* concr = *((PgfConcr**) value);
     PyPGFClosure* clo = (PyPGFClosure*) fn;
     
     PyObject* py_name = NULL;
     PyObject* py_lang = NULL;
     
-	py_name = gu2py_string(name);
+	py_name = PyString_FromString(name);
 	if (py_name == NULL) {
 		gu_raise(err, PgfExn);
 		goto end;
@@ -2012,12 +1971,12 @@ PGF_getLanguages(PGFObject *self, void *closure)
 static void
 pgf_collect_cats(GuMapItor* fn, const void* key, void* value, GuExn* err)
 {
-	PgfCId name = *((PgfCId*) key);
+	PgfCId name = (PgfCId) key;
     PyPGFClosure* clo = (PyPGFClosure*) fn;
     
     PyObject* py_name = NULL;
     
-	py_name = gu2py_string(name);
+	py_name = PyString_FromString(name);
 	if (py_name == NULL) {
 		gu_raise(err, PgfExn);
 		goto end;
@@ -2059,21 +2018,18 @@ PGF_getCategories(PGFObject *self, void *closure)
 static PyObject*
 PGF_getStartCat(PGFObject *self, void *closure)
 {
-	GuPool* tmp_pool = gu_local_pool();
+    return PyString_FromString(pgf_start_cat(self->pgf));
-	PyObject* pyname = gu2py_string(pgf_start_cat(self->pgf, tmp_pool));
-	gu_pool_free(tmp_pool);
-    return pyname;
 }
 
 static void
 pgf_collect_funs(GuMapItor* fn, const void* key, void* value, GuExn* err)
 {
-	PgfCId name = *((PgfCId*) key);
+	PgfCId name = (PgfCId) key;
     PyPGFClosure* clo = (PyPGFClosure*) fn;
     
     PyObject* py_name = NULL;
     
-	py_name = gu2py_string(name);
+	py_name = PyString_FromString(name);
 	if (py_name == NULL) {
 		gu_raise(err, PgfExn);
 		goto end;
@@ -2115,19 +2071,17 @@ PGF_getFunctions(PGFObject *self, void *closure)
 static PyObject*
 PGF_functionsByCat(PGFObject* self, PyObject *args)
 {
-	const char *catname_s;
+	PgfCId catname;
-    if (!PyArg_ParseTuple(args, "s", &catname_s))
+    if (!PyArg_ParseTuple(args, "s", &catname))
         return NULL;
 
-	GuPool *tmp_pool = gu_local_pool();
-    GuString catname = gu_str_string(catname_s, tmp_pool);
-
 	PyObject* functions = PyList_New(0);
 	if (functions == NULL) {
-		gu_pool_free(tmp_pool);
 		return NULL;
 	}
 
+	GuPool *tmp_pool = gu_local_pool();
+
 	// Create an exception frame that catches all errors.
 	GuExn* err = gu_new_exn(NULL, gu_kind(type), tmp_pool);
 
@@ -2146,20 +2100,14 @@ PGF_functionsByCat(PGFObject* self, PyObject *args)
 static TypeObject*
 PGF_functionType(PGFObject* self, PyObject *args)
 {
-	const char *funname_s;
+	PgfCId funname;
-    if (!PyArg_ParseTuple(args, "s", &funname_s))
+    if (!PyArg_ParseTuple(args, "s", &funname))
         return NULL;
 
-	GuPool *tmp_pool = gu_local_pool();
-    GuString funname = gu_str_string(funname_s, tmp_pool);
-    
     PgfType* type =
 		pgf_function_type(self->pgf, funname);
-
-	gu_pool_free(tmp_pool);
-
 	if (type == NULL) {
-		PyErr_Format(PyExc_KeyError, "Function '%s' is not defined", funname_s);
+		PyErr_Format(PyExc_KeyError, "Function '%s' is not defined", funname);
 		return NULL;
 	}
 
@@ -2179,10 +2127,10 @@ PGF_generateAll(PGFObject* self, PyObject *args, PyObject *keywds)
 {
 	static char *kwlist[] = {"cat", "n", NULL};
 
-	const char *catname_s;
+	PgfCId catname;
 	int max_count = -1;
     if (!PyArg_ParseTupleAndKeywords(args, keywds, "s|i", kwlist,
-                                     &catname_s, &max_count))
+                                     &catname, &max_count))
         return NULL;
 
 	IterObject* pyres = (IterObject*)
@@ -2201,7 +2149,6 @@ PGF_generateAll(PGFObject* self, PyObject *args, PyObject *keywds)
 	pyres->container = (PyObject*) pyres;
 
 	GuPool *tmp_pool = gu_local_pool();
-    GuString catname = gu_str_string(catname_s, tmp_pool);
 
 	pyres->res =
 		pgf_generate_all(self->pgf, catname, pyres->pool);
@@ -2245,7 +2192,7 @@ PGF_graphvizAbstractTree(PGFObject* self, PyObject *args) {
 	}
 
 	GuString str = gu_string_buf_freeze(sbuf, tmp_pool);
-	PyObject* pystr = gu2py_string(str);
+	PyObject* pystr = PyString_FromString(str);
 
 	gu_pool_free(tmp_pool);
 	return pystr;