instance method

Array#keep_if

() { (Elem item) -> ::boolish } -> self

() -> ::Enumerator[Elem, self]

keep_if {|element| ... } → self

keep_if → new_enumerator

static VALUE
rb_ary_keep_if(VALUE ary)
{
    RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
    rb_ary_select_bang(ary);
    return ary;
}

With a block given, calls the block with each element of self; removes the element from self if the block does not return a truthy value:

Example

a = [:foo, 'bar', 2, :bam]
a.keep_if {|element| element.to_s.start_with?('b') } # => ["bar", :bam]

With no block given, returns a new Enumerator.

See also #join #last #intersection #length also in 4.1 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0