[Python-ideas] where statement in Pyret

[Nick Coghlan]

On 10 November 2013 19:55, Tarek Ziadé <tarek at ziade.org> wrote:
> From the documentation example:
>
> fun sum(l):
>   cases(List) l:
>     | empty => 0
>     | link(first, rest) => first + sum(rest)
>   end
> where:
>   sum([]) is 0
>   sum([1, 2, 3]) is 6
> end

It would make more sense to just bake py.test style rich assertions
into the language in some way and let people write:

    def sum(iterable):
        # implementation of sum

    assert sum([]) == 0
    assert sum([1, 2, 3]) == 6

A mechanism to say "always execute assert statements in this module
regardless of optimisation level" could also be useful.

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia