To retain external white space while collapsing internal white space:

use strict;
use warnings;

my $str = "  Hello\n\t\n   World  \n";
print ">$str<\n";
$str =~ s/\b\s+\b/ /g;
print ">$str<\n";

[download]

Prints:

>  Hello
    
   World  
<
>  Hello World  
<

[download]
DWIM is Perl's answer to Gödel

In reply to Re: How to remove \n between two words but retain one space by GrandFather
in thread How to remove \n between two words but retain one space by Anonymous Monk

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