work on type inference some more

[ccc.git] / sem / hm / subst.h

diff --git a/sem/hm/subst.h b/sem/hm/subst.h
new file mode 100644 (file)
index 0000000..ffec9a7
--- /dev/null
+++ b/sem/hm/subst.h
@@ -0,0 +1,24 @@
+#ifndef SEM_HM_SUBST_H
+#define SEM_HM_SUBST_H
+
+#include "../../ast.h"
+#include "../hm.h"
+
+struct subst {
+       int nvar;
+       char **vars;
+       struct type **types;
+};
+
+struct subst *subst_id();
+struct subst *subst_singleton(char *ident, struct type *t);
+struct subst *subst_union(struct subst *l, struct subst *r);
+
+struct type *subst_apply_t(struct subst *subst, struct type *l);
+struct scheme *subst_apply_s(struct subst *subst, struct scheme *scheme);
+struct gamma *subst_apply_g(struct subst *subst, struct gamma *gamma);
+
+void subst_print(struct subst *s, FILE *out);
+void subst_free(struct subst *s, bool type);
+
+#endif