From: tho_mica_l <micathom@...>
Date: 2008-01-31T05:29:58+09:00
Subject: Re: Proposal/RFQ: Hash#values/keys with block

> "Give me the keys of the hash with a value over 200."
>
> hash.keys {|k,v| v > 200 }

Well, from my POV this is rather a special case of a more general
method
somewhere between inject and find_all that IMHO is missing somehow,
i.e.
a find_all that allow users to define the value to be stored -- so
it's
actually inject()?

> Sure can this be solved in several other ways, but I think this would
> be the most direct and intuitive way.

Apart from the fact that my opinion on this doesn't matter, I'm
slightly
concerned with a core/stdlib coded in C growing too large/complex.

> Please, everybody post your opinions. I would especially be happy if
> somebody would express some support to my position...

After all you only have to convince one person since there is no ruby
committee I would know of. :-)

> How could you return the keys without iterating over them?

Uhm ... well ... BTW the code you're looking for is in hash.c:

    static VALUE
    rb_hash_keys(VALUE hash)
    {
        VALUE ary;

        ary = rb_ary_new();
        rb_hash_foreach(hash, keys_i, ary);

        return ary;
    }

Regards,
Thomas.