This is a little weird. Can somebody explain this.
#!/usr/bin/perl -w
$_ = "The quick\n\nbrown fox\njumped.";
print "-------------\n";
foreach (/(.*)$/gm){
print "[$_]\n";
}
print "-------------\n";
foreach (/^(.*)/gm){
print "[$_]\n";
}
print "-------------\n";
foreach (/^(.*)$/gm){
print "[$_]\n";
}
print "-------------\n";
Produces the following
-------------
[The quick]
[]
[]
[brown fox]
[]
[jumped.]
[]
-------------
[The quick]
[]
[brown fox]
[jumped.]
-------------
[The quick]
[]
[brown fox]
[jumped.]
-------------
Even though I found a solution to the problem, I still don't have an explanation for it. Does anybody know what is going on in the engine?
I've added
use re qw(debug); to the script and looked and in the first example it says it matched 0 of 32767 times when the position is still on character 9. On the second set, this doesn't happen. How is this matching twice on the first time.
Also I tried this
#!/usr/bin/perl -w
$_ = "The quick\n\nbrown fox\njumped.";
print "-------------\n";
foreach (/(?:^|\G)(.*)/gm){
print "[$_]\n";
}
print "-------------\n";
And look what it did
-------------
[The quick]
[]
[]
[brown fox]
[]
[jumped.]
[]
-------------
Hmmmmmmm.
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