Re^2: removing the white spaces

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Re^3: removing the white spaces by Tanalis (Curate) on Apr 13, 2006 at 14:00 UTC
It does? Why's that, then? -- Tanalis `#include www.liquidfusion.org.uk`	[reply]
Re^4: removing the white spaces by japhy (Canon) on Apr 13, 2006 at 14:27 UTC
I've mentioned this before, I'll explain it again. The substitution `s/^\s+//` is simple and direct: replace a chunk of whitespace at the beginning of the string with nothing. The substitution `s/\s+$//` is simple and almost as direct: replace a chunk of whitespace followed by the end of the string with nothin. Sadly, it's not as "perfect" as the first one -- it matches each chunk of whitespace and examines it to see if it's at the end of the string or not. Oh well. When you say `s/^\s+\|\s+$//g`, perl's regex engine gets stupid. Real dumb. It tries BOTH branches of that regex at every location in the string. EVERY LOCATION! EVEN WHERE THERE AREN'T SPACES! See for yourself with `perl -mre=debug -e '$_ = " a b c "; s/^\s+\|\s+$//g'` It's upsetting! So do it with two regexes. Give peace a chance. Jeff `japhy` Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and `perl` hacker How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart	[reply] [d/l] [select]
Re^3: removing the white spaces by codeacrobat (Chaplain) on Apr 13, 2006 at 14:20 UTC
A noncapturing solution should speed things. untested: `s/(?:^\s+)\|(?:\s+$)//g` [download]	[reply] [d/l]
Re^4: removing the white spaces by japhy (Canon) on Apr 13, 2006 at 14:21 UTC
First, the `(?:...)`'s aren't needed. Second, that's still no good. Jeff `japhy` Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and `perl` hacker How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart	[reply] [d/l]


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