WIP

src/libponyc/codegen/genmatch.c

@@ -754,11 +754,7 @@ LLVMValueRef gen_match(compile_t* c, ast_t* ast)
     ast_free_unattached(type);
   }
 
-  ast_t* expr_type = deferred_reify(reify, ast_type(match_expr), c->opt);
-  ast_t* match_type = alias(expr_type);
-
-  if(match_type != expr_type)
-    ast_free_unattached(expr_type);
+  ast_t* match_type = deferred_reify(reify, ast_type(match_expr), c->opt);
 
   LLVMValueRef match_value = gen_expr(c, match_expr);
 

src/libponyc/expr/match.c

@@ -497,17 +497,20 @@ bool expr_case(pass_opt_t* opt, ast_t* ast)
   if(!infer_pattern_type(pattern, match_type, opt))
     return false;
 
-  ast_t* pattern_type = make_pattern_type(opt, pattern);
+  ast_t* declared_pattern_type = make_pattern_type(opt, pattern);
+  if(declared_pattern_type == NULL)
+    return false;
+
+  ast_settype(ast, declared_pattern_type);
 
+  ast_t* pattern_type = consume_type(declared_pattern_type, TK_NONE, false);
   if(pattern_type == NULL)
     return false;
 
-  ast_settype(ast, pattern_type);
-
   bool ok = true;
   errorframe_t info = NULL;
 
-  switch(is_matchtype(match_type, pattern_type, &info, opt))
+  switch(is_matchtype(match_type, declared_pattern_type, &info, opt))
   {
     case MATCHTYPE_ACCEPT:
       break;
@@ -542,6 +545,8 @@ bool expr_case(pass_opt_t* opt, ast_t* ast)
       ast_error_frame(&frame, pattern, "pattern type: %s",
         ast_print_type(pattern_type));
       errorframe_append(&frame, &info);
+      ast_error_frame(&frame, match_expr,
+        "the match expression with the inadequate capability is here");
       errorframe_report(&frame, opt->check.errors);
 
       ok = false;
@@ -579,6 +584,9 @@ bool expr_case(pass_opt_t* opt, ast_t* ast)
         "guard must be a boolean expression");
     }
   }
+
+  ast_free_unattached(pattern_type);
+
   return ok;
 }
 

src/libponyc/expr/operator.c

@@ -551,7 +551,7 @@ static bool add_as_type(pass_opt_t* opt, ast_t* ast, ast_t* expr,
 
       ast_t* expr_type = ast_type(expr);
       errorframe_t info = NULL;
-      matchtype_t is_match = is_matchtype(expr_type, type, &info, opt);
+      matchtype_t is_match = is_matchtype2(expr_type, type, &info, opt);
       if(is_match == MATCHTYPE_DENY_CAP)
       {
         errorframe_t frame = NULL;

src/libponyc/type/matchtype.c

@@ -5,6 +5,7 @@
 #include "typeparam.h"
 #include "viewpoint.h"
 #include "ponyassert.h"
+#include "alias.h"
 
 static matchtype_t is_x_match_x(ast_t* operand, ast_t* pattern,
   errorframe_t* errorf, bool report_reject, pass_opt_t* opt);
@@ -578,8 +579,9 @@ static matchtype_t is_nominal_match_entity(ast_t* operand, ast_t* pattern,
 
   // If the operand does provide the pattern, but the operand refcap can't
   // match the pattern refcap, deny the match.
-  if(!is_cap_sub_cap(ast_id(o_cap), TK_EPHEMERAL,
-    ast_id(p_cap), ast_id(p_eph)))
+  //printf("----> o_cap: %d, o_eph: %d, p_cap: %d, p_eph: %d\n", ast_id(o_cap), ast_id(o_eph), ast_id(p_cap), ast_id(p_eph));
+  if(!is_cap_sub_cap(ast_id(o_cap), ast_id(o_eph),
+     ast_id(p_cap), ast_id(p_eph)))
   {
     if(errorf != NULL)
     {
@@ -589,6 +591,16 @@ static matchtype_t is_nominal_match_entity(ast_t* operand, ast_t* pattern,
         ast_print_type(operand), ast_print_type(pattern),
         ast_print_type(o_cap), ast_print_type(o_eph),
         ast_print_type(p_cap), ast_print_type(p_eph));
+
+        if(is_cap_sub_cap(ast_id(o_cap), TK_EPHEMERAL, ast_id(p_cap),
+          ast_id(p_eph)))
+          ast_error_frame(errorf, o_cap,
+            "this would be possible if the subcap were more ephemeral. "
+            "Perhaps you meant to consume this variable");
+    }
+    else
+    {
+      printf("----> errorf is NULL\n");
     }
 
     return MATCHTYPE_DENY_CAP;
@@ -922,6 +934,21 @@ static matchtype_t is_x_match_x(ast_t* operand, ast_t* pattern,
 
 matchtype_t is_matchtype(ast_t* operand, ast_t* pattern, errorframe_t* errorf,
   pass_opt_t* opt)
+{
+  ast_t* consumed_pattern = consume_type(pattern, TK_NONE, false);
+  if (consumed_pattern == NULL)
+    return MATCHTYPE_REJECT;
+
+  matchtype_t rslt = is_x_match_x(operand, consumed_pattern, errorf, true, opt);
+
+  // TODO this seems to segfault
+  //ast_free_unattached(consumed_pattern);
+
+  return rslt;
+}
+
+matchtype_t is_astype(ast_t* operand, ast_t* pattern, errorframe_t* errorf,
+  pass_opt_t* opt)
 {
   return is_x_match_x(operand, pattern, errorf, true, opt);
 }

src/libponyc/type/matchtype.h

@@ -44,6 +44,14 @@ typedef enum
 matchtype_t is_matchtype(ast_t* operand, ast_t* pattern, errorframe_t* errorf,
   pass_opt_t* opt);
 
+/**
+ * Same as is_matchtype() but specifically designed to work with `as` which
+ * under the steed model, needs to act differently than matchwith respect
+ * to iso.
+ */
+matchtype_t is_astype(ast_t* operand, ast_t* pattern, errorframe_t* errorf,
+  pass_opt_t* opt);
+
 PONY_EXTERN_C_END
 
 #endif

src/libponyc/type/subtype.c

@@ -147,7 +147,7 @@ static bool is_sub_cap_and_eph(ast_t* sub, ast_t* super, check_cap_t check_cap,
           ast_id(super_eph)))
           ast_error_frame(errorf, sub_cap,
             "this would be possible if the subcap were more ephemeral. "
-            "Perhaps you meant to consume a variable here");
+            "Perhaps you meant to consume this variable");
       }
 
       return false;