Perhaps something like this, which will remove all whitespace except for newlines, if your line is in $line. 
$line =~ s/[^\S\n]+//g;

[download]
If you need to remove just trailing whitespace, change it to this: 
$line =~ s/[^\S\n]+$//g;

[download]

Update: I should point out explicitly that that's a capital S inside the character class... the character class matches anything that's non-non-whitespace (i.e., whitespace) and non-newline.

-- Mike

--
just,my${.02}

In reply to Re: removing all whitespace but newlines by thelenm
in thread removing all whitespace but newlines by blacksmith

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