method

assoc

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

assoc(p1) public

Searches through an array whose elements are also arrays comparing obj with the first element of each contained array using obj.==. Returns the first contained array that matches (that is, the first associated array), or nil if no match is found. See also Array#rassoc.

   s1 = [ "colors", "red", "blue", "green" ]
   s2 = [ "letters", "a", "b", "c" ]
   s3 = "foo"
   a  = [ s1, s2, s3 ]
   a.assoc("letters")  #=> [ "letters", "a", "b", "c" ]
   a.assoc("foo")      #=> nil

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/* 
 *  call-seq:
 *     array.assoc(obj)   ->  an_array  or  nil
 *
 *  Searches through an array whose elements are also arrays
 *  comparing _obj_ with the first element of each contained array
 *  using obj.==.
 *  Returns the first contained array that matches (that
 *  is, the first associated array),
 *  or +nil+ if no match is found.
 *  See also <code>Array#rassoc</code>.
 *
 *     s1 = [ "colors", "red", "blue", "green" ]
 *     s2 = [ "letters", "a", "b", "c" ]
 *     s3 = "foo"
 *     a  = [ s1, s2, s3 ]
 *     a.assoc("letters")  #=> [ "letters", "a", "b", "c" ]
 *     a.assoc("foo")      #=> nil
 */

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

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

assoc

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