TIP #20: ADD C LOCALE-EXACT CTYPE FUNCTIONS 
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 Version:      $Revision: 1.4 $
 Author:       Jeffrey Hobbs <jeff.hobbs_at_acm.org>
 State:        Deferred
 Type:         Project
 Tcl-Version:  8.5
 Vote:         Pending
 Created:      Monday, 08 January 2001
 URL:          https://tip.tcl-lang.org20.html
 Post-History: 

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 ABSTRACT 
==========

 This TIP adds functions to Tcl that are a subset of the standard ctype 
 functions (isspace, isalpha, ...) that are ensured to operate only in 
 the C locale (char < 0x80). 

 RATIONALE 
===========

 Tcl used to force the C locale everywhere in order to have parsing work 
 as expected throughout Tcl, but that prevented certain i18n features 
 from working correctly (like native character input). In enabling the 
 i18n features, some bugs (like 
 [<URL:http://sf.net/bugs/?func=detailbug&bug_id=127512&group_id=10894>]) 
 were exposed that required the C locale to be enabled to function 
 properly. Since we don't want to force that requirement, creating ctype 
 functions that work as if they were always in the C locale is the best 
 solution. 

 REFERENCE IMPLEMENTATION 
==========================

 Add a file /generic/tclC.c/ (to parallel /generic/tclUtf.c/) that 
 contains functions following the convention C_isspace, C_isalpha, ... 
 These functions would use character or bit maps to ensure greatest 
 speed and efficiency of the functions. 

 Not all use of the ctype functions need be replaced. Those that walk 
 over a string, especially backwards, are the ones that need 
 replacement. 

 COPYRIGHT 
===========

 This document is in the public domain.  

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