[racket] Immutable vectors

At Thu, 05 Sep 2013 09:01:58 -0600,
Neil Toronto wrote:
> The best advice I have is to keep performance-critical loops either all
> typed or all untyped, unless the only things that cross the contract
> boundary are flat first-order datums like flonums, strings and
> vectors. (The math library's flonum functions, for example, are plenty
> fast to call from untyped code.) Speeding up the contract boundary is an
> active area of research, so I expect to have to modify this advice in
> the future.

If you want to know whether contract checking overhead is significant
for your program (and which contracts are most expensive), you can use
the contract profiler in the `contract-profile' library.

Vincent