From: Phrogz <phrogz@...>
Date: 2009-11-15T13:51:01+09:00
Subject: Re: Array.assoc

On Nov 14, 9:48 pm, Phrogz <phr...@mac.com> wrote:
> On Nov 14, 9:31 pm, Ralph Shnelvar <ral...@dos32.com> wrote:
>
> > If I want to find the source to the Class Array ... specifically
> > Array.assoc ... where would I look?
>
> Slim2:~ phrogz$ cd /usr/local/src/ruby-1.9.1-p243/
> Slim2:ruby-1.9.1-p243 phrogz$ grep -E "define_method.+assoc" *.c
> array.c:    rb_define_method(rb_cArray, "assoc", rb_ary_assoc, 1);
> array.c:    rb_define_method(rb_cArray, "rassoc", rb_ary_rassoc, 1);
> hash.c:    rb_define_method(rb_cHash, "assoc", rb_hash_assoc, 1);
> hash.c:    rb_define_method(rb_cHash, "rassoc", rb_hash_rassoc, 1);
>
> So, look for the function named rb_cArray in the array.c file in the
> ruby source code.

Bah, of course I meant rb_ary_assoc. Looking at your pasted text while
typing is bad. :p

As penance, here is the source code for that function:

VALUE
rb_ary_assoc(VALUE ary, VALUE key)
{
    long i;
    VALUE v;

    for (i = 0; i < RARRAY_LEN(ary); ++i) {
	v = rb_check_array_type(RARRAY_PTR(ary)[i]);
	if (!NIL_P(v) && RARRAY_LEN(v) > 0 &&
	    rb_equal(RARRAY_PTR(v)[0], key))
	    return v;
    }
    return Qnil;
}