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instance method

Array#filter

() { (Elem element) -> ::boolish } -> ::Array[Elem]

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

filter {|element| ... } → new_array

filter → new_enumerator

static VALUE
rb_ary_select(VALUE ary)
{
    VALUE result;
    rb_len_t i;

    RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
    result = rb_ary_new2(RARRAY_LEN(ary));
    for (i = 0; i < RARRAY_LEN(ary); i++) {
        if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
            rb_ary_push(result, rb_ary_elt(ary, i));
        }
    }
    return result;
}

Alias of #select

With a block given, calls the block with each element of self; returns a new array containing those elements of self for which the block returns a truthy value:

Example

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

With no block given, returns a new Enumerator.

Related: see Methods for Fetching.

See also #select #filter! #fill #fetch_values also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0

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