If you try to call split in a scalar context you will recieve: "Use of implicit split to @_ is deprecated". The code will run, and will be slightly faster: 
       Five: 13 wallclock secs (13.39 usr +  0.00 sys = 13.39 CPU) @  
+5.15/s (n=69)
       One: 13 wallclock secs (12.92 usr +  0.01 sys = 12.93 CPU) @  4
+.87/s (n=63)

[download]
(relevant code:) 
        One   => sub { my ($y) = (split(/\s+/,$testlarge))[0]; },
        Five  => sub { my  $y  =  split(/\s+/,$testlarge)      }

[download]
While a tad faster, using something besides split (such as a regex) show that split doesn't optimize away the other entries. See my other post on this thread for more benchmark results.

Ciao,
Gryn

In reply to Calling split in a scalar context by gryng
in thread is split optimized? by Anonymous Monk

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