Esteemed Monks,

I have a problem with -F switch. I HAVE gone through one-liner perldocumentation.

Assume I want to write every second character from input. I wrote code which works fine:

ls -al | perl -lne '@F=split //; $i=0; @a = map {$i++%2 ? $_ : " "} @F; print @a;'

But my question is why the code below does not work? I.e. it produces blank output:

ls -al | perl -F// -lne '$i=0; @a = map {$i++%2 ? $_ : " "} @F; print @a;'

perl -h clearly states that:

-F/pattern/     split() pattern for -a switch (//'s are optional)

and -a is described as:

-a              autosplit mode with -n or -p (splits $_ into @F)

I use "perl, v5.8.3 built for x86_64-linux-thread-multi"

Thank you for your patience,
bfilipow-the-wisdom-seeker

Thank you again wise monks

In reply to Perl oneliner problem with -F switch by bfilipow

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