Re^3: trim leading & trailing whitespace

$_ = "   no  \n   \n   \n    they    \n \n    won't     \n\n\n";
s/^\s*(.*?)\s*$/$1/gm;
print;
[download]

Result:

no
they
won't

All blank lines are gone.

Comment on Re^3: trim leading & trailing whitespace Download Code

Replies are listed 'Best First'.
Re^4: trim leading & trailing whitespace by thinker (Parson) on Mar 30, 2005 at 10:33 UTC
Hi bart, I see what you mean now. I thought you were suggesting it would remove the newline characters, not just the blank lines. Your way is more correct. cheers thinker	[reply]
Re^4: trim leading & trailing whitespace by tlm (Prior) on Mar 30, 2005 at 10:41 UTC
How about this: `$_ = " yes \n \n \n they \n \n will \n\n\n"; s/^\s?(?:\b(.?)\s*?)?(\n)?$/$1$2/gm; print; __END__ % perl 443391.pl yes they will` [download] the lowliest monk	[reply] [d/l]
Re^5: trim leading & trailing whitespace by bart (Canon) on Mar 30, 2005 at 11:10 UTC
Danger, don't use `\b` if you want to detect the edges between spaces an nonspaces. It won't work for nonspace+nonword characters, like quotes and punctuation. Perhaps replace the `\b(.?)` with `(\S.?)`. Still, you're not running this with warnings enabled, are you? Both $1 and $2 are optional, so both can be undef, but you use their value regardless. This runs without warnings: `s/^\s?((?:\S.?)?)\s*?(\n?)$/$1$2/gm;` [download]	[reply] [d/l]