Tab Stop Converter

This snippet turns tabs into "jump to the next multiple of four" padding. This is useful for programs in which tab-stops are hardcoded to a fixed location, rather than a fixed length. (Came out of a comment made by davido in the chatterbox.)

Update:

Two strokes of credited to davido ...

Update:

Modification to allow arbitrary tab stop length.

$_="1\t12\t123\t1234\t12345\t";
$s=4;split/\t/;print map{$_.=q/ /x$s;substr $_,0,$s*int(length($_)/$s)
+}@_;
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Comment on Tab Stop Converter Download Code

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Re: Tab Stop Converter by davido (Cardinal) on Sep 29, 2003 at 06:34 UTC
Here it is as a Swiss Army One Liner. First idsfa's golfed to 85 keystrokes: `perl -pi -e 'split/\t/;map{$_.=q/ /x4;substr$_,0,4*int length($_)/4}@_ +' filename.txt` [download] And atcroft's golfed to 78 keystrokes: `perl -pi -e 'while(/\t/g){$d=(4-pos%4)%4+1;$x=q/ /x$d;s/\t/$x/}' filen +ame.txt` [download] ...both in convenient one line form for your tab-conversion-pleasure. ;) Fun exercise. Thanks for the snippets idsfa and atcroft. You guys had working versions while I was still working out the logic on mine (which never saw the light of day). Dave "If I had my life to do over again, I'd be a plumber." -- Albert Einstein	[reply] [d/l] [select]
Re: Tab Stop Converter by atcroft (Abbot) on Sep 29, 2003 at 06:37 UTC
Does this code do the same, if the value for $ts is set appropriately? `perl -p -i.bak -e '$ts=12; while (m/\t/g) { $d= ($ts - (pos % $ts)) % $ts + 1; $x = " " x $d; s/\t/$x/; }' filename.txt` (I know the -i.bak will create a backup file, but I tend to do that at least until I'm sure I have a replacement working...)	[reply] [d/l]
Re: Tab Stop Converter by jmcnamara (Monsignor) on Sep 29, 2003 at 22:11 UTC
See also How do I expand tabs in a string? in perlfaq4. -- John.	[reply]
Re: Tab Stop Converter by bsb (Priest) on Oct 02, 2003 at 08:48 UTC
Is there code somewhere that will guess the tabstop size? I'd like to hook it up to vim so that perl/C/etc sets the tab size as the original author uses (modelines obviously won't do)	[reply]