but it looks like 'strict' isn't active within the evalled code by default

By default it isn't, due to this piece of nonsense from Benchmark.pm:

# evaluate something in a clean lexical environment sub _doeval { no strict; eval shift }

If you remove the no strict; as I have, then you'd have got:

For 10 elements: runloop unable to compile ' my @res = zip( @a, @b ) ': Global symbol "@a" requires explicit package name at (eval 4) line 1. Global symbol "@b" requires explicit package name at (eval 4) line 1. code: sub { for (1 .. 1) { local $_; package main; my @res = zip( @ +a, @b ) ;} } at c:\test\junk9.pl line 29

Which seems far more useful than the current behaviour. I'm not sure what the author hoped to achieve by adding it?

The other thing to note in my version is the assignment of the result. Without this, Perl may optimise away code that appears in a void context. In 5.10 for example, map called in a void context doesn't bother stacking the results which would further skew the benchmark.


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In reply to Re^6: Making a hash with lists by BrowserUk
in thread Making a hash with lists by knarf

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