libpgf: few fixes to make the loading of grammars with def rules possible

src/runtime/c/pgf/data.c

@@ -160,10 +160,7 @@ GU_DEFINE_TYPE(
 		PGF_PATT_APP, PgfPattApp,
 		GU_MEMBER(PgfPattApp, ctor, PgfCId),
 		GU_MEMBER(PgfPattApp, n_args, GuLength),
-		GU_MEMBER(PgfPattApp, args, PgfPatt)),
+		GU_FLEX_MEMBER(PgfPattApp, args, PgfPatt)),
-	GU_CONSTRUCTOR_S(
-		PGF_PATT_LIT, PgfPattLit,
-		GU_MEMBER(PgfPattLit, lit, PgfLiteral)),
 	GU_CONSTRUCTOR_S(
 		PGF_PATT_VAR, PgfPattVar,
 		GU_MEMBER(PgfPattVar, var, PgfCId)),
@@ -173,6 +170,9 @@ GU_DEFINE_TYPE(
 		GU_MEMBER(PgfPattAs, patt, PgfPatt)),
 	GU_CONSTRUCTOR(
 		PGF_PATT_WILD, void),
+	GU_CONSTRUCTOR_S(
+		PGF_PATT_LIT, PgfPattLit,
+		GU_MEMBER(PgfPattLit, lit, PgfLiteral)),
 	GU_CONSTRUCTOR_S(
 		PGF_PATT_IMPL_ARG, PgfPattImplArg,
 		GU_MEMBER(PgfPattImplArg, patt, PgfPatt)),
@@ -184,7 +184,7 @@ GU_DEFINE_TYPE(
 	PgfEquation, struct, 
 	GU_MEMBER(PgfEquation, body, PgfExpr),
 	GU_MEMBER(PgfEquation, n_patts, GuLength),
-	GU_MEMBER(PgfEquation, patts, PgfPatt));
+	GU_FLEX_MEMBER(PgfEquation, patts, PgfPatt));
 
 // Distinct type so we can give it special treatment in the reader
 GU_DEFINE_TYPE(PgfEquationsM, GuSeq, gu_type(PgfEquation));

src/runtime/c/pgf/data.h

@@ -274,6 +274,8 @@ typedef struct {
 } PgfProductionConst;
 
 
+extern GU_DECLARE_TYPE(PgfPatt, GuVariant);
+
 extern GU_DECLARE_TYPE(PgfProduction, GuVariant);
 extern GU_DECLARE_TYPE(PgfBindType, enum);
 extern GU_DECLARE_TYPE(PgfLiteral, GuVariant);
@@ -286,10 +288,10 @@ pgf_literal_cat(PgfLiteral lit);
 
 typedef enum {
 	PGF_PATT_APP,
-	PGF_PATT_LIT,
 	PGF_PATT_VAR,
 	PGF_PATT_AS,
 	PGF_PATT_WILD,
+	PGF_PATT_LIT,
 	PGF_PATT_IMPL_ARG,
 	PGF_PATT_TILDE,
 	PGF_PATT_NUM_TAGS

src/runtime/c/pgf/expr.c

@@ -117,7 +117,7 @@ GU_DEFINE_TYPE(
 		GU_MEMBER(PgfExprMeta, id, int)),
 	GU_CONSTRUCTOR_S(
 		PGF_EXPR_FUN, PgfExprFun,
-		GU_MEMBER(PgfExprFun, fun, GuStr)),
+		GU_MEMBER(PgfExprFun, fun, GuString)),
 	GU_CONSTRUCTOR_S(
 		PGF_EXPR_VAR, PgfExprVar,
 		GU_MEMBER(PgfExprVar, var, int)),

src/runtime/c/pgf/reader.c

@@ -516,7 +516,7 @@ pgf_read_to_GuSeq(GuType* type, PgfReader* rdr, void* to)
 }
 
 static void
-pgf_read_to_maybe_seq(GuType* type, PgfReader* rdr, void* to)
+pgf_read_to_PgfEquationsM(GuType* type, PgfReader* rdr, void* to)
 {
 	GuSeq* sto = to;
 	uint8_t tag = pgf_read_u8(rdr);
@@ -525,9 +525,32 @@ pgf_read_to_maybe_seq(GuType* type, PgfReader* rdr, void* to)
 	case 0:
 		*sto = gu_null_seq;
 		break;
-	case 1:
+	case 1: {
-		pgf_read_to_GuSeq(type, rdr, to);
+        GuLength length = pgf_read_len(rdr);
+        gu_return_on_exn(rdr->err, );
+
+        GuSeq seq = gu_new_seq(PgfEquation*, length, rdr->opool);
+        PgfEquation** data = gu_seq_data(seq);
+        for (size_t i = 0; i < length; i++) {
+            GuLength n_patts = pgf_read_len(rdr);
+            gu_return_on_exn(rdr->err, );
+
+            PgfEquation *equ =
+                gu_malloc(rdr->opool, 
+                          sizeof(PgfEquation)+sizeof(PgfPatt)*n_patts);
+            equ->n_patts = n_patts;
+            for (int j = 0; j < n_patts; j++) {
+                pgf_read_to(rdr, gu_type(PgfPatt), &equ->patts[j]);
+                gu_return_on_exn(rdr->err, );
+            }
+            pgf_read_to(rdr, gu_type(PgfExpr), &equ->body);
+            gu_return_on_exn(rdr->err, );
+
+            data[i] = equ;
+        }
+        *sto = seq;
 		break;
+    }
 	default:
 		gu_raise_i(rdr->err, PgfReadTagExn,
 			   .type = type, .tag = tag);
@@ -775,7 +798,7 @@ pgf_read_to_table = GU_TYPETABLE(
 	PGF_READ_TO(GuString),
 	PGF_READ_TO(double),
 	PGF_READ_TO(pointer),
-	PGF_READ_TO_FN(PgfEquationsM, pgf_read_to_maybe_seq),
+	PGF_READ_TO(PgfEquationsM),
 	PGF_READ_TO(GuSeq),
 	PGF_READ_TO(PgfCCatId),
 	PGF_READ_TO(PgfCCat),