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instance method

Hash#to_proc

() -> ^(K) -> V?

to_proc → proc

static VALUE
rb_hash_to_proc(VALUE hash)
{
    return rb_func_lambda_new(hash_proc_call, hash, 1, 1);
}

Returns a Proc object that maps a key to its value:

Example

h = {foo: 0, bar: 1, baz: 2}
proc = h.to_proc
proc.class # => Proc
proc.call(:foo) # => 0
proc.call(:bar) # => 1
proc.call(:nosuch) # => nil
h.default_proc = proc { |hash, key| "Missing key: #{key}" } # This affect the existing proc object
proc.call(:nosuch) # => "Missing key: #{nosuch}"

Related: see Methods for Converting.

See also #to_hash #to_s #to_h #transform_keys also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0

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