Looking for white spaces between words

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

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Re: Looking for white spaces between words by Enlil (Parson) on Jun 10, 2004 at 20:31 UTC
`$foo =~ s/( {2,})/" " x length($1)/ge` -enlil	[reply] [d/l]
Re^2: Looking for white spaces between words by bradcathey (Prior) on Jun 10, 2004 at 20:47 UTC
That works great to replace all spaces. However, as a casual observer, I'm not sure this is what was asked. Were all the spaces to be replaced with the non-breaking spaces, or just those after the first one, leaving one space without the replacement. So: `"the lazy  brown   fox    jumped..."` [download] But I would like to expand the question a bit. I would like to see all spaces removed with the exception of just one separating the words, and then have that replace with the non-breaking space. So: `"the lazy brown fox jumped..."` [download] —Brad "A little yeast leavens the whole dough."	[reply] [d/l] [select]
Re^3: Looking for white spaces between words by Enlil (Parson) on Jun 10, 2004 at 20:55 UTC
That works great to replace all spaces. However, as a casual observer, I'm not sure this is what was asked. Were all the spaces to be replaced with the non-breaking spaces, or just those after the first one, leaving one space without the replacement. So: `"the lazy  brown   fox    jumped..."` [download] This should work: `$foo =~ s/(?<= )( +)/' ' x length($1)/ge` [download] But I would like to expand the question a bit. I would like to see all spaces removed with the exception of just one separating the words, and then have that replace with the non-breaking space. So: `"the lazy brown fox jumped..."` [download] Can be solved thusly: `$foo =~ s/ {2,}/ /g;` [download] I believe this answers both requests unless I am misreading something. -enlil	[reply] [d/l] [select]
Re: Looking for white spaces between words by elusion (Curate) on Jun 10, 2004 at 20:41 UTC
Well, let's go through this a step at a time. You want to search for 2 or more consecutive spaces. There are two ways to do that: `/ +/` and `/ {2,}/`. I normally use the first one, as that's what I think looks best. Second, you want to make a substitution. Enter `$var =~ s/.../.../;`. Now we have this: `$foo =~ s/( +)//;`. We just need to come up with something to substitute in there. Well, you want ` ` for each space, so we want it repeated for the length of the spaces: `" " x length $1`. Now to add that to our regular expression. The trick is to use the /e and /g modifiers, which interpret the second half of the substitution as an expression and substitute globally. `$foo =~ s/( +)/" " x length $1/ge` And that's it! You're done! Hope this helps, elusion : http://matt.diephouse.com	[reply] [d/l] [select]
Re: Looking for white spaces between words by Roy Johnson (Monsignor) on Jun 10, 2004 at 21:17 UTC
Just for fun, a lookaround solution. When you find a space preceded by a space, or a space followed by a space, replace it: `s/(?<= ) \| (?= )/ /g;` [download] The PerlMonk `tr///` Advocate	[reply] [d/l]
Re: Looking for white spaces between words by fletcher_the_dog (Friar) on Jun 10, 2004 at 20:37 UTC
As an alternate solution to what you appear to be trying to do you could try: `my $foo = "the lazy brown fox jumped..."; $foo = "<pre>$foo</pre>";` [download] The "pre" tag preserves white space in html.	[reply] [d/l]