From: nobu@...
Date: 2014-07-10T00:45:54+00:00
Subject: [ruby-core:63617] [ruby-trunk - Bug #10022] [Rejected] Inconsistent behavior of gsub replacement

Issue #10022 has been updated by Nobuyoshi Nakada.

Description updated
Status changed from Open to Rejected

The second argument is evaluated **before** calling `gsub` method.
Call it with a block:

~~~ruby
puts str.gsub(/(CFBundleVersion<\/key>\n\t.*\.).*(<\/string>)/) {"#{$1}#{ver}#{$2}"}
~~~

----------------------------------------
Bug #10022: Inconsistent behavior of gsub replacement
https://bugs.ruby-lang.org/issues/10022#change-47670

* Author: Frank Luan
* Status: Rejected
* Priority: Normal
* Assignee: 
* Category: regexp
* Target version: 
* ruby -v: ruby 2.1.2p95 (2014-05-08 revision 45877) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
In the following code, the two gsub's yield different results. ([[https://gist.github.com/franklsf95/6c0f8938f28706b5644d]])

~~~ruby
ver = 9999
str = "\t<key>CFBundleDevelopmentRegion</key>\n\t<string>en</string>\n\t<key>CFBundleVersion</key>\n\t<string>0.1.190</string>\n\t<key>AppID</key>\n\t<string>000000000000000</string>"
puts str.gsub /(CFBundleVersion<\/key>\n\t.*\.).*(<\/string>)/, "#{$1}#{ver}#{$2}"
puts '--------'
puts str.gsub /(CFBundleVersion<\/key>\n\t.*\.).*(<\/string>)/, "#{$1}#{ver}#{$2}"
~~~

My running result is:

~~~
<key>CFBundleDevelopmentRegion</key>
<string>en</string>
<key>9999
<key>AppID</key>
<string>000000000000000</string>
--------
<key>CFBundleDevelopmentRegion</key>
<string>en</string>
<key>CFBundleVersion</key>
<string>0.1.9999</string>
<key>AppID</key>
<string>000000000000000</string>
~~~

...which is strangely inconsistent.



-- 
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