I'd think about using:  &Frobnitz($_) if index $_, '@'; instead. I got this: 
        Rate regexp  index
regexp 826/s     --   -10%
index  921/s    11%     --

with Benchmark. Why throw the regex engine at a single character when there is lovely little function just for that? =)

In reply to Re: Regex anchor speed ?: Is /^.*X/ faster than /X/ ? by extremely
in thread Regex anchor speed ?: Is /^.*X/ faster than /X/ ? by cshirky

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