Method: Hash#metch

Defined in:

lib/core_ext/hash.rb

#metch(search, default = :__n_o_n_e__) ⇒ Object

Returns a value from the hash for the matching key

Similar to fetch, search the hash keys for the search string and return the corresponding value. Unlike fetch, however, if a hash key is a Regexp, the search argument is matched against this Regexp. The hash is searched in its natural order.

Examples:

h = { /aa/ => :aa, /a/ => :a, 'b' => :b }
h.metch('abc')          # => :a
h.metch('bcd')          # => KeyError
h.metch('b')            # => :b
h.metch('x', :foobar)   # => :foobar

Parameters:

• search (String) —

  string to search or matche against

• default (Object) (defaults to: :__n_o_n_e__) —

  fallback value if no key matched

Returns:

• (Object) —

  hash value

Raises:

• (KeyError) —

  no key matched and no default given

# File 'lib/core_ext/hash.rb', line 21

def metch(search, default=:__n_o_n_e__)
  fetch search
rescue KeyError
  each do |key, value|
    next unless key.is_a? Regexp
    return value if key.match? search
  end
  raise(KeyError, "no match found: #{search.inspect}") if default == :__n_o_n_e__
  default
end