instance method
Enumerable#filter_map
[U] () { (Elem elem) -> (nil | false | U) } -> ::Array[U]
() -> ::Enumerator[Elem, ::Array[untyped]]
filter_map {|element| ... } → array
filter_map → enumerator
enum.c
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static VALUE
enum_filter_map(VALUE obj)
{
VALUE ary;
RETURN_SIZED_ENUMERATOR(obj, 0, 0, enum_size);
ary = rb_ary_new();
rb_block_call(obj, id_each, 0, 0, filter_map_i, ary);
return ary;
}
Returns an array containing truthy elements returned by the block.
With a block given, calls the block with successive elements; returns an array containing each truthy value returned by the block:
Example
(0..9).filter_map {|i| i * 2 if i.even? } # => [0, 4, 8, 12, 16] {foo: 0, bar: 1, baz: 2}.filter_map {|key, value| key if value.even? } # => [:foo, :baz]
When no block given, returns an Enumerator.