As gellyfish correctly states, substr() is being used as an lvalue here, i.e. something you can assign to. In this case, you are replacing five characters (the third argument) of $DATE, starting at position two (the second argument, and counting from 0) with the concatenation $YEAR.$MONTH. Hence the output you observe.

CU
Robartes-

In reply to Re: What is substring working on here. by robartes
in thread What is substring working on here. by Scarborough

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