Method: Enumerable#each_cons

Defined in:
enum.c

#each_cons(n) { ... } ⇒ self #each_cons(n) ⇒ Object

Calls the block with each successive overlapped n-tuple of elements; returns self:

a = []
(1..5).each_cons(3) {|element| a.push(element) }
a # => [[1, 2, 3], [2, 3, 4], [3, 4, 5]]

a = []
h = {foo: 0,  bar: 1, baz: 2, bam: 3}
h.each_cons(2) {|element| a.push(element) }
a # => [[[:foo, 0], [:bar, 1]], [[:bar, 1], [:baz, 2]], [[:baz, 2], [:bam, 3]]]

With no block given, returns an Enumerator.

Overloads:

  • #each_cons(n) { ... } ⇒ self

    Yields:



3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
 
# File 'enum.c', line 3297

static VALUE
enum_each_cons(VALUE obj, VALUE n)
{
    long size = NUM2LONG(n);
    struct MEMO *memo;
    int arity;

    if (size <= 0) rb_raise(rb_eArgError, "invalid size");
    RETURN_SIZED_ENUMERATOR(obj, 1, &n, enum_each_cons_size);
    arity = rb_block_arity();
    if (enum_size_over_p(obj, size)) return obj;
    memo = MEMO_NEW(rb_ary_new2(size), dont_recycle_block_arg(arity), size);
    rb_block_call(obj, id_each, 0, 0, each_cons_i, (VALUE)memo);

    return obj;
}