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# Demonstrates that we have a compatibility fix to mathn's weird idea of
# integer mathematics.
# This was contributed by Jonathan Hinkle (https://github.com/hynkle). Thanks!
$:.unshift File.dirname(__FILE__) + "/../lib"
require 'parslet'
require 'parslet/convenience'
include Parslet
def attempt_parse
possible_whitespace = match['\s'].repeat
cephalopod =
str('octopus') |
str('squid')
parenthesized_cephalopod =
str('(') >>
possible_whitespace >>
cephalopod >>
possible_whitespace >>
str(')')
parser =
possible_whitespace >>
parenthesized_cephalopod >>
possible_whitespace
# This parse fails, but that is not the point. When mathn is in the current
# ruby environment, it modifies integer division in a way that makes
# parslet loop indefinitely.
parser.parse %{(\nsqeed)\n}
rescue Parslet::ParseFailed
end
attempt_parse
puts 'it terminates before we require mathn'
puts "requiring mathn now"
# mathn was deprecated as of Ruby 2.5
if RUBY_VERSION.gsub(/[^\d]/, '').to_i < 250
require 'mathn'
end
puts "and trying again (will hang without the fix)"
attempt_parse # but it doesn't terminate after requiring mathn
puts "okay!"
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