character from middle

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: character from middle by Utilitarian (Vicar) on Sep 01, 2009 at 09:10 UTC
So you don't want to remove a literal + followed by an end of string or preceded by a start of string. You could lookahead and lookbehind for not start/end of string. Take a look in perlre for `(?!pattern)` and `(?<!pattern)`	[reply] [d/l] [select]
Re: character from middle by jwkrahn (Abbot) on Sep 01, 2009 at 09:26 UTC
`#!/usr/bin/perl use warnings; use strict; while ( <DATA> ) { my @x; push @x, $-[ 0 ] while /\+/g; substr $_, $x[ @x / 2 ], 1, ''; print; } __DATA__ + 5 + 45 +` [download]	[reply] [d/l]
Re: character from middle by JavaFan (Canon) on Sep 01, 2009 at 09:53 UTC
You need to do it in three steps. First you count the number of '+'s. Second, you decide which one is the middle. Third, you remove that one from string.	[reply]
Re: character from middle by ig (Vicar) on Sep 01, 2009 at 13:48 UTC
You should think about how "the middle one" is different from the others and you should think about other data records and what you want done with them. What results would you want with the following lines? `+ 1 + 2 + 3 + + 1 + 2 + 3 + 4 + +1+2+3+ +1+2+3+4+ ++1+2++ 1 + 2 1 + 2 + 3 1 + 2 + 3 + 4` [download]	[reply] [d/l]
Re: character from middle by arun_kom (Monk) on Sep 01, 2009 at 09:26 UTC
Modifying your code like so seems to work. `while(<DATA>){ s/(.+)\+(.+)/$1$2/g; print $_; }` [download] A better way could be the one mentioned in the above post.	[reply] [d/l]
Re^2: character from middle by Utilitarian (Vicar) on Sep 01, 2009 at 09:35 UTC
Consider the data `__DATA__ + 5 + 23 + 223 + 34 + 45 +` [download] Your solution will remove the last instance of "+" ie. `+ 5 + 23 + 223 + 34 45 +` [download] Depends on the expected data and required result, the presence of the `/g` operator made me suspect that the above data was likely	[reply] [d/l] [select]