Class: Hash

Inherits:
Object show all
Defined in:
lib/core_ext/hash.rb

Direct Known Subclasses

AIPP::THash

Instance Method Summary collapse

Instance Method Details

#metch(search, default = nil) ⇒ 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 string is matched against this Regexp. The hash is searched in it's 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: nil)

    fallback value if no key matched

Returns:

Raises:

  • (KeyError)

    no key matched and no default given


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

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