Re: tr faster than eq?

When the code is evalled, your lexical $string is not in scope, so all these tests are running against undef.

If I change the declaration to our $string, and refer to $::string within all the evals I get:

             Rate tr_loop eq_loop      tr      eq
tr_loop   96844/s      --    -26%    -96%    -98%
eq_loop  130666/s     35%      --    -95%    -97%
tr      2436420/s   2416%   1765%      --    -41%
eq      4137436/s   4172%   3066%     70%      --
[download]

which seems more reasonable.

Hugo

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Re^2: tr faster than eq? by Keystroke (Scribe) on Mar 10, 2005 at 18:37 UTC
That explains my benchmark code results. But I still have conflicting results from -Devel::SmallProf for execution times between tr and eq. `count wall tm cpu time line 16183 0.197199 0.700000 368: next unless ($_ = ($_ =~ tr/1/1/)); count wall tm cpu time line 16183 0.282621 0.750000 369: next if ($_ eq '0000000000000'); 15923 0.157497 0.890000 370: $_ = ($_ =~ tr/1/1/);` [download]	[reply] [d/l]
Re^2: tr faster than eq? by Anonymous Monk on Mar 11, 2005 at 09:15 UTC
Changing the 'my' to 'our' is enough to do the trick. Changing '$string' to '$::string' isn't necessary; the Benchmark module runs the code in the package of the caller.	[reply]