I get the same results with perl 5.10.0. In perl 5.8.8, the results are different:
$b matches $test
$a = (?x-ism:Hello\#\ World\\E
)
$b = (?x-ism:Hello\#\ World
)

[download]
Seems like a bug to me. What is the code's behaviour in 5.12?

In reply to Re: Weird quoting with /x modifier by choroba
in thread Weird quoting with /x modifier by ykar

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