My question is why perl do not support chr('0b'.$1)
Because chr takes a number as an argument. You pass it a string - a string that doesn't look like a number. The "0b" only works for numeric literals, or arguments to oct and hex. '0b' . $1 is not a literal.
Is there a way to convert a string to number explicitly like perl6?
eval, as in 
$string =~ s/ (\d+)/chr eval "0b$1"/egx;

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In reply to Re: what is difference between chr and oct? by JavaFan
in thread what is difference between chr and oct? by xiaoyafeng

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