P.S. I have re-written chapter 3 of the style guide in particular 3.3 and 3.6 to add your idea:
http://www.ccs.neu.edu/home/matthias/Style/style/Units_of_Code.html On Mar 5, 2013, at 9:59 AM, Matthias Felleisen wrote: > > 1. Clutter removal is built into Racket: > > (define-syntax (interface stx) > (syntax-case stx (subject-to) > [(interface name clauses ...) > ;; ==> > .. (provide (contract-out ..) ..) ..])) > > The above macro has become a standard in my recent projects where I place it > into my ./Lib/contract.rkt library. It is part of an effort to develop a > header-file style for Racket. And it is an effort to supply a way to > selectively check contracts. [More soon. It is NOT about turning contracts > off.] > > 2. Contract test issue acknowledged. I have run into this problem too during > my recent construction of a game program. My work-around > > 3. Clutter removal is built into Racket: > > #lang racket > > #lang racket > > (define-syntax-rule > (tmod def-or-exp ...) > (module* test racket > (require rackunit (submod "..")) > (check-equal? 1 1) > def-or-exp ...)) > > ;; ----------------------------------------- > > (provide > (contract-out > (f (-> integer? integer?)))) > > (define (f x) x) > > (tmod (check-equal? (f 2) 2) > (check-equal? (f 3) 2)) > > Consider adding the above module to your ./Lib/contract.rkt library. > > > > > > > On Mar 5, 2013, at 8:39 AM, Greg Hendershott wrote: > >> Not to flog this, but: >> >> Lately I've been trying to be a good little doobie and use `(provide >> (contract-out))` instead of `define/contract`. Although it's more >> typing/clutter, grumble grumble, I've been getting used to it. >> >> Unfortunately I discovered one gotcha: Using (module+ test <rackunit >> tests>) means that the test bypasses the contract -- because it's a >> submodule, and the contract is on the module boundary. So my unit >> tests weren't exercising and validating the contract. I missed a buggy >> contract this way. >> >> In hindsight this is all perfectly obvious. Just not from the guide. >> To be fair using submodules for tests is a relatively recent practice >> in Racket. But I wanted to point out the interaction in case it helps >> anyone else who is trying to use module contracts and do unit tests >> following the curent examples. >> >> One way to avoid this problem is instead of module+ use module*: >> >> (module* test racket ;; To test module-boundary contracts, must use >> ;; module* and (require (submod "..")). >> (require (submod "..")) >> ... check check check ... >> ) >> >> Of course this adds even more "clutter", but it works. >> >> On Thu, Dec 27, 2012 at 3:31 PM, Matthias Felleisen >> <matth...@ccs.neu.edu> wrote: >>> >>> I have added a note on this issue to the Style issue; see section 3.6. >>> Strictly speaking, this prose probably belongs into the Contract guide. -- >>> Matthias >>> >>> >>> >>> On Nov 30, 2012, at 5:17 PM, Ryan Culpepper wrote: >>> >>>> You can have mutually recursive functions with define/contract, but you >>>> can't with submodules. >>>> >>>> Ryan >>>> >>>> On 11/30/2012 05:04 PM, Ray Racine wrote: >>>>> Why not make this explicit by deprecating define/contract and support >>>>> this use case with a submodule. They lightweight enough and makes >>>>> boundary demarcations consistent, explicit and simple. Module -> >>>>> boundary. >>>>> >>>>> On Nov 30, 2012 12:05 PM, "Matthias Felleisen" <matth...@ccs.neu.edu >>>>> <mailto:matth...@ccs.neu.edu>> wrote: >>>>> >>>>> >>>>> On Nov 30, 2012, at 10:15 AM, Greg Hendershott wrote: >>>>> >>>>>>> This is a complete misunderstanding. >>>>>> >>>>>> Sometimes I feel like a kid in the room while the adults are talking. >>>>>> When it comes to contracts, I have to stipulate that most of you are >>>>>> smarter than me and have thought about this longer than me. >>>>> >>>>> >>>>> Apologies. My opening wasn't meant to say "I am smarter" but I wanted >>>>> to send a strong message about define/contract. It really introduces a >>>>> boundary and in some strange sense your (possibly misleading) >>>>> microbenchmark >>>>> exposes this constraint too. >>>>> >>>>> >>>>> >>>>> ____________________ >>>>> Racket Users list: >>>>> http://lists.racket-lang.org/users >>>>> >>>>> >>>>> >>>>> ____________________ >>>>> Racket Users list: >>>>> http://lists.racket-lang.org/users >>>>> >>>> >>>> ____________________ >>>> Racket Users list: >>>> http://lists.racket-lang.org/users >>> >>> >>> ____________________ >>> Racket Users list: >>> http://lists.racket-lang.org/users > > > ____________________ > Racket Users list: > http://lists.racket-lang.org/users ____________________ Racket Users list: http://lists.racket-lang.org/users
