[TCLCORE] TIP #358: Suppress Empty List Element Generation from the Split Command
by George Petasis other posts by this author
Oct 6 2009 10:09AM messages near this date
Re: [TCLCORE] CFV TIP #348 - Substituted 'errorStack' / 'traceback'
|
Re: [TCLCORE] TIP #358: Suppress Empty List Element Generation from the Split Command
TIP #358: SUPPRESS EMPTY LIST ELEMENT GENERATION FROM THE SPLIT COMMAND
=========================================================================
Version: $Revision: 1.2 $
Author: George Petasis <petasis_at_iit.demokritos.gr>
State: Draft
Type: Project
Tcl-Version: 8.7
Vote: Pending
Created: Sunday, 04 October 2009
URL: http://purl.org/tcl/tip/358.html
WebEdit: http://purl.org/tcl/tip/edit/358
Post-History:
-------------------------------------------------------------------------
ABSTRACT
==========
The *split* command will create empty list elements when adjacent split
characters are found in the input. In some cases these empty list
elements are not desired, so this TIP proposes a new switch to disable
their generation.
RATIONALE
===========
The idea for this TIP came from a discussion in comp.lang.tcl:
[<URL:http://groups.google.gr/group/comp.lang.tcl/browse_thread/thread/8d46b0f10e7a5750/d78
44cc739aa4310> ]
and the (non obvious) suggestions on how tokens can be extracted from a
string can be performed efficiently.
It should be noted that this will allow the *split* command to be used
in a fashion that is very similar to how splitting works in many other
languages (e.g., Perl, awk, Unix shells).
SPECIFICATION
===============
This TIP proposes a new optional switch (*-noemptyelements*) to the
*split* command:
*split -noemptyelements* /string/ ?/splitChars/?
If this option is present, then *split* will not produce an empty list
element when the /string/ contains adjacent characters that are present
in /splitChars/.
REFERENCE IMPLEMENTATION
==========================
Currently there is no patch, but it should be quite easy to implement
this.
COPYRIGHT
===========
This document has been placed in the public domain.
-------------------------------------------------------------------------
TIP AutoGenerator - written by Donal K. Fellows
------------------------------------------------------------------------------
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
_______________________________________________
Tcl-Core mailing list
Tcl-Core@[...].net
https://lists.sourceforge.net/lists/listinfo/tcl-core
Thread:
George Petasis
Tom Jackson
Andreas Kupries
Andreas Kupries
Donald Arseneau
Twylite
Magentus
Jordan Henderson
Joe English
Donal K. Fellows
Georgios Petasis
Andreas Kupries
Georgios Petasis
|