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instance method

Hash#delete

(::Hash::_Key key) -> V?

[T, K2 < ::Hash::_Key] (K2 key) { (K2 key) -> T } -> (T | V)

delete(key) → value or nil

delete(key) {|key| ... } → object

static VALUE
rb_hash_delete_m(VALUE hash, VALUE key)
{
    VALUE val;

    rb_hash_modify_check(hash);
    val = rb_hash_delete_entry(hash, key);

    if (!UNDEF_P(val)) {
        compact_after_delete(hash);
        return val;
    }
    else {
        if (rb_block_given_p()) {
            return rb_yield(key);
        }
        else {
            return Qnil;
        }
    }
}

If an entry for the given key is found, deletes the entry and returns its associated value; otherwise returns nil or calls the given block.

With no block given and key found, deletes the entry and returns its value:

Example

h = {foo: 0, bar: 1, baz: 2}
h.delete(:bar) # => 1
h # => {foo: 0, baz: 2}

With no block given and key not found, returns nil.

With a block given and key found, ignores the block, deletes the entry, and returns its value:

Example

h = {foo: 0, bar: 1, baz: 2}
h.delete(:baz) { |key| raise 'Will never happen'} # => 2
h # => {foo: 0, bar: 1}

With a block given and key not found, calls the block and returns the block’s return value:

Example

h = {foo: 0, bar: 1, baz: 2}
h.delete(:nosuch) { |key| "Key #{key} not found" } # => "Key nosuch not found"
h # => {foo: 0, bar: 1, baz: 2}

Related: see Methods for Deleting.

See also #default_proc= #delete_if #default_proc #dig also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0

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