method

cycle

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

cycle(...) public

Calls block for each element repeatedly n times or forever if none or nil is given. If a non-positive number is given or the array is empty, does nothing. Returns nil if the loop has finished without getting interrupted.

   a = ["a", "b", "c"]
   a.cycle {|x| puts x }  # print, a, b, c, a, b, c,.. forever.
   a.cycle(2) {|x| puts x }  # print, a, b, c, a, b, c.

Show source

/*
 *  call-seq:
 *     ary.cycle {|obj| block }
 *     ary.cycle(n) {|obj| block }
 *  
 *  Calls <i>block</i> for each element repeatedly _n_ times or
 *  forever if none or nil is given.  If a non-positive number is
 *  given or the array is empty, does nothing.  Returns nil if the
 *  loop has finished without getting interrupted.
 *     
 *     a = ["a", "b", "c"]
 *     a.cycle {|x| puts x }  # print, a, b, c, a, b, c,.. forever.
 *     a.cycle(2) {|x| puts x }  # print, a, b, c, a, b, c.
 *     
 */

static VALUE
rb_ary_cycle(argc, argv, ary)
    int argc;
    VALUE *argv;
    VALUE ary;
{
    long n, i;
    VALUE nv = Qnil;

    rb_scan_args(argc, argv, "01", &nv);

    RETURN_ENUMERATOR(ary, argc, argv);
    if (NIL_P(nv)) {
        n = -1;
    }
    else {
        n = NUM2LONG(nv);
        if (n <= 0) return Qnil;
    }

    while (RARRAY(ary)->len > 0 && (n < 0 || 0 < n--)) {
        for (i=0; i<RARRAY(ary)->len; i++) {
            rb_yield(RARRAY(ary)->ptr[i]);
        }
    }
    return Qnil;
}

cycle

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