# String#to_proc
#
# See https://raganwald.com/2007/10/stringtoproc.html ( Subscribe in a reader)
#
# Ported from the String Lambdas in Oliver Steele's Functional Javascript
# http://osteele.com/sources/javascript/functional/
#
# This work is licensed under the MIT License:
#
# (c) 2007 Reginald Braithwaite
# Portions Copyright (c) 2006 Oliver Steele
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
unless ''.respond_to?(:to_proc)
&block
params = []
expr = self
sections = expr.split(/\s*->\s*/m)
if sections.length > 1 then
eval sections.reverse!.inject {|e, p| "(Proc.new { | | })" }, block && block.binding
elsif expr.match(/\b_\b/)
eval "Proc.new { |_| }", block && block.binding
else
leftSection = expr.match(/^\s*(?:[+*\/%&|\^\.=<>\[]|!=)/m)
rightSection = expr.match(/[+\-*\/%&|\^\.=<>!]\s*$/m)
if leftSection || rightSection then
if (leftSection) then
params.push('$left')
expr = '$left' + expr
end
if (rightSection) then
params.push('$right')
expr = expr + '$right'
end
else
self.gsub(
/(?:\b[A-Z]|\.[a-zA-Z_$])[a-zA-Z_$\d]*|[a-zA-Z_$][a-zA-Z_$\d]*:|self|arguments|'(?:[^'\\]|\\.)*'|"(?:[^"\\]|\\.)*"/, ''
).scan(
/([a-z_$][a-z_$\d]*)/i
) do |v|
params.push(v) unless params.include?(v)
end
end
eval "Proc.new { | | }", block && block.binding
end
end
end
end