Orchid Fairy (兰花仙子) wrote:
> Hi,
>
> # perl -le '$_="aXXXb"; print "one word is $1" while(/(X*)/g);'
> one word is
> one word is XXX
> one word is
> one word is
>
>
> what are the three empty values in the output?
Adding pos() (see `perldoc -f pos`) shows what is happening:
$ perl -le '$_="aXXXb"; print "one word is $1 at ", pos while(/(X*)/g);'
one word is at 0
one word is XXX at 4
one word is at 4
one word is at 5
$ perl -le '$_="aaXXXbb"; print "one word is $1 at ", pos while(/(X*)/g);'
one word is at 0
one word is at 1
one word is XXX at 5
one word is at 5
one word is at 6
one word is at 7
It seems to be picking up an extra empty string after a non-zero length
match.
Also:
$ perl -le '$_="aXXXb"; @captured = $_ =~ m{ (X*) }gmsx;print "captured:
<", join( ">, <",@captured), ">"'
captured: <>, <XXX>, <>, <>
--
Just my 0.00000002 million dollars worth,
Shawn
Programming is as much about organization and communication
as it is about coding.
I like Perl; it's the only language where you can bless your
thingy.
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