and -a is described as: -a autosplit mode with -n or -p (splits $_ into @F)

yes, but you ommitted the -a switch from your 2nd one-liner.
You didn't need it in the first one because you explicity declared @F

The following works fine for me: 

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

[download]

Cheers,
Darren :)

In reply to Re: Perl oneliner problem with -F switch by McDarren
in thread Perl oneliner problem with -F switch by bfilipow

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