A simple expedient for deriving a boolean value from index is to use 1+index(...). If the value is not found, you get 0. If it is found at the start of the string, you get 1.

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
"Memory, processor, disk in that order on the hardware side. Algorithm, algorithm, algorithm on the code side." - tachyon

In reply to Re^3: Metacharacters in regex expression by BrowserUk
in thread Metacharacters in regex expression by bubulik

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