method

find_index

v1_8_7_72 - Show latest stable - 0 notes - Class: Enumerable

find_index(...) public

Compares each entry in enum with value or passes to block. Returns the index for the first for which the evaluated value is non-false. If no object matches, returns nil

   (1..10).find_index  {|i| i % 5 == 0 and i % 7 == 0 }   #=> nil
   (1..100).find_index {|i| i % 5 == 0 and i % 7 == 0 }   #=> 34
   (1..100).find_index(50)                                #=> 49

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/*
 *  call-seq:
 *     enum.find_index(value)            => int or nil
 *     enum.find_index {| obj | block }  => int or nil
 *
 *  Compares each entry in <i>enum</i> with <em>value</em> or passes
 *  to <em>block</em>.  Returns the index for the first for which the
 *  evaluated value is non-false.  If no object matches, returns
 *  <code>nil</code>
 *
 *     (1..10).find_index  {|i| i % 5 == 0 and i % 7 == 0 }   #=> nil
 *     (1..100).find_index {|i| i % 5 == 0 and i % 7 == 0 }   #=> 34
 *     (1..100).find_index(50)                                #=> 49
 *
 */

static VALUE
enum_find_index(argc, argv, obj)
    int argc;
    VALUE *argv;
    VALUE obj;
{
    VALUE memo[3];      /* [return value, current index, condition value] */
    rb_block_call_func *func;

    if (argc == 0) {
        RETURN_ENUMERATOR(obj, 0, 0);
        func = find_index_iter_i;
    }
    else {
        rb_scan_args(argc, argv, "1", &memo[2]);
        if (rb_block_given_p()) {
            rb_warn("given block not used");
        }
        func = find_index_i;
    }

    memo[0] = Qnil;
    memo[1] = 0;
    rb_block_call(obj, id_each, 0, 0, func, (VALUE)memo);
    return memo[0];
}

find_index

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