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instance method

Enumerable#partition

enum.partition { |obj| block } → [ true_array, false_array ]

enum.partition → an_enumerator

static VALUE
enum_partition(VALUE obj)
{
    struct MEMO *memo;

    RETURN_SIZED_ENUMERATOR(obj, 0, 0, enum_size);

    memo = MEMO_NEW(rb_ary_new(), rb_ary_new(), 0);
    rb_block_call(obj, id_each, 0, 0, partition_i, (VALUE)memo);

    return rb_assoc_new(memo->v1, memo->v2);
}

Returns two arrays, the first containing the elements of enum for which the block evaluates to true, the second containing the rest.

If no block is given, an enumerator is returned instead.

Example

(1..6).partition { |v| v.even? }  #=> [[2, 4, 6], [1, 3, 5]]

See also #one? #reduce #none? #reject also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.1

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