You can nearly do this with just <> and without touching @ARGV. First read eof then consider:

while( <> ) { print "First: $_"; last if eof; # Stop at end of /first/ file } while( <> ) { print; }

But this actually does special processing of the first non-empty file, not the first file. Detecting that the first file is non-empty without directly modifying @ARGV is trickier:

my $args= @ARGV; if( ! eof() # Prime the <> pump && @ARGV == $args-1 # Did we not move past the first file? ) { while( <> ) { print "First: $_"; last if eof; } } while( <> ) { print; }

In any case, I find it an interesting solution.

(Updated within seconds of posting to replace a near solution with a real solution.)

- tye        


In reply to Re: diamond operator (eof) by tye
in thread diamond operator by Anonymous Monk

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