[plt-scheme] contract questions--convention for "any" conflict and inline documentation

From: Rob Hunter (rob.hunter at gmail.com)
Date: Fri Nov 21 17:39:54 EST 2008

I'm new to contracts, and had a couple of questions for the community:

(1) If I try to do a simple (require scheme/contracts), I run up
against a conflict with SRFI-1 "any" and the contract "any".  I'm
doing this right now, but was wondering if this was a common enough
issue that a convention has been established:

(rename-in scheme/contract
                  (any c:any))

(2) I like the idea of using contracts as a way of augmenting the
documentation of a function.  My vision is to do use a convention like
this for certain functions:

;; my-great-fn
;; squares any number you give it.
(provide/contract (my-great-fn (-> number? number?)))
(define (my-great-fn n)
  (* n n))

This is all well and good, except that I can no longer have
my-great-fn in the (provide ...) form at the top of my module.  I
really like provide as an "always there" source of documenting what
this module provides.  So, I'm considering using the following
"comment convention", but does anyone have a better idea?

#lang scheme/base

(require ...)


  ;; provided with contracts:
  ;; my-great-fn

... impl ...


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