[racket-dev] Blame and re-provided bindings

From: Stevie Strickland (sstrickl at ccs.neu.edu)
Date: Fri Jan 14 16:28:25 EST 2011

On Jan 14, 2011, at 4:22 PM, Robby Findler wrote:
> No, actually in this case the user message is also wrong. If you trace
> thru the module dag, you'll see it.

Just to check, are you talking about the second series of modules, or the first?  The problem in the first is likely a variation of PR11084, as Ryan said.  In the second, I get:

contract violation: expected <integer?>, given: 3.5
  contract on f from (file /Users/sstrickl/c.rkt) via (file /Users/sstrickl/a.rkt), blaming (file /Users/sstrickl/b.rkt)
  contract: (-> integer? integer?)
        at: /Users/sstrickl/c.rkt:4.1

and if I'm breaking that text down correctly, that's:

positive: c
user: a
negative: b

Which seems right to me, according to what I said.  That is, b entered into a contract with c about value f.  b reprovided f (with no contract) to a, who actually used the value via the expression `(f 3.5)'.

So a misused the value, but b was responsible for its misuse (since it gave it to a without any additional protection).  This is, of course, going by the interpretation of uncontracted reprovides being equivalent to reproviding with the contract any/c.

Have I missed anything here?

Stevie

Posted on the dev mailing list.