Class: Array

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

Overview

Copyright © 2010-2013 Michael Dvorkin

Awesome Print is freely distributable under the terms of MIT license. See LICENSE file or www.opensource.org/licenses/mit-license.php


The following makes it possible to invoke awesome_print while performing operations on method arrays, ex:

ap [].methods - Object.methods
ap ''.methods.grep(/!|\?/)

If you could think of a better way please let me know :-)

Instance Method Summary collapse

Instance Method Details

#grep(pattern, &blk) ⇒ Object


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# File 'lib/awesome_print/core_ext/array.rb', line 33

def grep(pattern, &blk)
  #
  # The following looks rather insane and I've sent numerous hours trying
  # to figure it out. The problem is that if grep gets called with the
  # block, for example:
  #
  #    [].methods.grep(/(.+?)_by/) { $1.to_sym }
  #
  # ...then simple:
  #
  #    original_grep(pattern, &blk)
  #
  # doesn't set $1 within the grep block which causes nil.to_sym failure.
  # The workaround below has been tested with Ruby 1.8.7/Rails 2.3.8 and
  # Ruby 1.9.2/Rails 3.0.0. For more info see the following thread dating
  # back to 2003 when Ruby 1.8.0 was as fresh off the grill as Ruby 1.9.2
  # is in 2010 :-)
  #
  # http://www.justskins.com/forums/bug-when-rerouting-string-52852.html
  #
  # BTW, if you figure out a better way of intercepting Array#grep please
  # let me know: twitter.com/mid -- or just say hi so I know you've read
  # the comment :-)
  #
  arr = unless blk
    original_grep(pattern)
  else
    original_grep(pattern) do |match|
      #
      # The binding can only be used with Ruby-defined methods, therefore
      # we must rescue potential "ArgumentError: Can't create Binding from
      # C level Proc" error.
      #
      # For example, the following raises ArgumentError since #succ method
      # is defined in C.
      #
      # [ 0, 1, 2, 3, 4 ].grep(1..2, &:succ)
      #
      eval("%Q/#{match.to_s.gsub('/', '\/')}/ =~ #{pattern.inspect}", blk.binding) rescue ArgumentError
      yield match
    end
  end
  if self.instance_variable_defined?('@__awesome_methods__')
    arr.instance_variable_set('@__awesome_methods__', self.instance_variable_get('@__awesome_methods__'))
    arr.reject! { |item| !(item.is_a?(Symbol) || item.is_a?(String)) } # grep block might return crap.
  end
  arr
end

#original_grepObject

Intercepting Array#grep needs a special treatment since grep accepts an optional block.


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# File 'lib/awesome_print/core_ext/array.rb', line 32

alias :original_grep :grep