1 files changed, 80 insertions, 0 deletions
diff --git a/interpreter/syntax.h b/interpreter/syntax.h
new file mode 100644
index 0000000..05f09c7
--- /dev/null
+++ b/interpreter/syntax.h
@@ -0,0 +1,80 @@
+#ifndef _H_SYNTAX
+#define _H_SYNTAX
+
+/* TOKENS */
+
+typedef enum {
+	TOKEN_SEMICOLON, /* ; */
+	TOKEN_EQUALS,    /* = */
+	TOKEN_OPEN_SQ,   /* [ */
+	TOKEN_CLOSE_SQ,  /* ] */
+	TOKEN_OPEN_P,    /* ( */
+	TOKEN_CLOSE_P,   /* ) */
+	TOKEN_COMMA,     /* , */
+	TOKEN_COLON,     /* : */
+	TOKEN_NAME,
+	TOKEN_INT
+} token_kind;
+
+typedef struct {
+	token_kind kind;
+	void* var;
+} token;
+
+typedef struct token_list {
+	token elem;
+	struct token_list* rest;
+} token_list;
+
+void free_token(token*);
+void free_token_list(token_list*);
+
+/* ELEMENTS */
+
+typedef enum {
+	EXPR_INT,
+	EXPR_NAME,
+	EXPR_LIST,
+	EXPR_TUPLE,
+	EXPR_APP
+} expr_kind;
+
+typedef struct {
+	expr_kind kind;
+	void* var1;
+	void* var2;
+} expression;
+
+typedef struct arg_list {
+	expression elem;
+	struct arg_list* rest;
+} arg_list;
+
+typedef struct {
+	char* name;
+	arg_list* args;
+	expression rhs;
+} rewrite_rule;
+
+typedef struct fuspel {
+	rewrite_rule rule;
+	struct fuspel* rest;
+} fuspel;
+
+unsigned empty_args_list(arg_list*);
+
+void cpy_expression(expression* dst, expression* src);
+unsigned eq_expression(expression*, expression*);
+expression** flatten_app_args(expression*);
+
+void concat_fuspel(fuspel* start, fuspel* end);
+fuspel* push_fuspel(fuspel*);
+fuspel* pop_fuspel(fuspel*);
+fuspel* popn_fuspel(fuspel*, unsigned char);
+
+void free_expression(expression*);
+void free_arg_list(arg_list*);
+void free_rewrite_rule(rewrite_rule*);
+void free_fuspel(fuspel*);
+
+#endif