implemented readExpr & readType

src/runtime/c/pgf/expr.h

@@ -10,37 +10,37 @@ struct PgfType;
 /// A literal for an abstract syntax tree
 typedef variant PgfLiteral;
 
-struct PgfLiteralStr {
+struct PGF_INTERNAL_DECL PgfLiteralStr {
     static const uint8_t tag = 0;
 
 	PgfText val;
 } ;
 
-struct PgfLiteralInt {
+struct PGF_INTERNAL_DECL PgfLiteralInt {
     static const uint8_t tag = 1;
 
 	int val;
 } ;
 
-struct PgfLiteralFlt {
+struct PGF_INTERNAL_DECL PgfLiteralFlt {
     static const uint8_t tag = 2;
 
 	double val;
 };
 
-struct PgfHypo {
+struct PGF_INTERNAL_DECL PgfHypo {
 	PgfBindType bind_type;
 	ref<PgfText> cid;
 	ref<PgfType> type;
 };
 
-struct PgfType {
+struct PGF_INTERNAL_DECL PgfType {
 	ref<PgfVector<PgfHypo>> hypos;
     ref<PgfVector<PgfExpr>> exprs;
 	PgfText name;
 };
 
-struct PgfExprAbs {
+struct PGF_INTERNAL_DECL PgfExprAbs {
     static const uint8_t tag = 0;
     
 	PgfBindType bind_type;
@@ -48,45 +48,45 @@ struct PgfExprAbs {
 	PgfText name;
 };
 
-struct PgfExprApp {
+struct PGF_INTERNAL_DECL PgfExprApp {
     static const uint8_t tag = 1;
 
 	PgfExpr fun;
 	PgfExpr arg;
 };
 
-struct PgfExprLit {
+struct PGF_INTERNAL_DECL PgfExprLit {
     static const uint8_t tag = 2;
 
 	PgfLiteral lit;
 };
 
-struct PgfExprMeta {
+struct PGF_INTERNAL_DECL PgfExprMeta {
     static const uint8_t tag = 3;
 
 	PgfMetaId id;
 };
 
-struct PgfExprFun {
+struct PGF_INTERNAL_DECL PgfExprFun {
     static const uint8_t tag = 4;
 
 	PgfText name;
 };
 
-struct PgfExprVar {
+struct PGF_INTERNAL_DECL PgfExprVar {
     static const uint8_t tag = 5;
     
 	int var;
 };
 
-struct PgfExprTyped {
+struct PGF_INTERNAL_DECL PgfExprTyped {
     static const uint8_t tag = 6;
 
 	PgfExpr expr;
 	ref<PgfType> type;
 };
 
-struct PgfExprImplArg {
+struct PGF_INTERNAL_DECL PgfExprImplArg {
     static const uint8_t tag = 7;
 
 	PgfExpr expr;
@@ -108,4 +108,65 @@ uintptr_t pgf_unmarshall_expr(PgfUnmarshaller *u, PgfExpr e);
 PGF_INTERNAL_DECL
 uintptr_t pgf_unmarshall_type(PgfUnmarshaller *u, PgfType *tp);
 
+typedef struct PgfBind {
+    PgfBindType bind_type;
+    struct PgfBind *next;
+    PgfText var;
+} PgfBind;
+
+class PGF_INTERNAL_DECL PgfExprParser {
+    enum PGF_TOKEN_TAG {
+        PGF_TOKEN_LPAR,
+        PGF_TOKEN_RPAR,
+        PGF_TOKEN_LCURLY,
+        PGF_TOKEN_RCURLY,
+        PGF_TOKEN_QUESTION,
+        PGF_TOKEN_LAMBDA,
+        PGF_TOKEN_RARROW,
+        PGF_TOKEN_LTRIANGLE,
+        PGF_TOKEN_RTRIANGLE,
+        PGF_TOKEN_COMMA,
+        PGF_TOKEN_COLON,
+        PGF_TOKEN_SEMI,
+        PGF_TOKEN_WILD,
+        PGF_TOKEN_IDENT,
+        PGF_TOKEN_INT,
+        PGF_TOKEN_FLT,
+        PGF_TOKEN_STR,
+        PGF_TOKEN_UNKNOWN,
+        PGF_TOKEN_EOF,
+    };
+
+    PgfUnmarshaller *u;
+	PGF_TOKEN_TAG token_tag;
+	PgfText *token_value;
+    PgfText *inp;
+    const char *pos;
+    uint32_t ch;
+
+    uint32_t getc();
+    void putc(uint32_t ch);
+
+public:
+    PgfExprParser(PgfText* input, PgfUnmarshaller *unmarshaller);
+    ~PgfExprParser();
+
+    void str_char();
+    void token();
+    bool lookahead(int ch);
+
+    PgfBind *parse_bind(PgfBind *next);
+    PgfBind *parse_binds(PgfBind *next);
+
+
+    uintptr_t parse_arg();
+    uintptr_t parse_term();
+    uintptr_t parse_expr();
+
+    bool parse_hypos(size_t *n_hypos, PgfTypeHypo **hypos);
+    uintptr_t parse_type();
+
+    bool eof();
+};
+
 #endif /* EXPR_H_ */