in reply to Performance penalty of using qr//

FTR: I encountered (and probably described/reported it here, but I don't remember for sure), a similar disappointment many years ago.

My recollection of it is that a variable built using qr// was always reinterpreted at the point of interpolation into another qr// or a larger regex.

My conclusion was that like the /o modifier on regex, it was either never implemented, or was removed by an early bug fix.

See also 971076, but I'm almost sure there should be an earlier thread.

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