shithub: mc

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Give better context for errors in match statements.

    In the past, we gave bad context for match statements
    type errors, giving the error on the match line. Eg:

        var x : byte
        var y : byte[:]

        match y
        | ...:
        | foo:      x = 4oo
        ;;

    would error on 'match' and not on 'foo'. This simple
    change solves that prolem by passing the pattern value
    as context.

--- a/parse/infer.c

+++ b/parse/infer.c

@@ -1618,7 +1618,7 @@

                 fatal(n, "Can't match against a void type near %s", ctxstr(st, n->matchstmt.val));

             for (i = 0; i < n->matchstmt.nmatches; i++) {

                 infernode(st, &n->matchstmt.matches[i], ret, sawret);

-                unify(st, n, type(st, n->matchstmt.val), type(st, n->matchstmt.matches[i]->match.pat));

+                unify(st, n->matchstmt.matches[i]->match.pat, type(st, n->matchstmt.val), type(st, n->matchstmt.matches[i]->match.pat));

             }

             break;

         case Nmatch: