My implementation in the perl core was a compromise between complexity, performance and convenience. It's currently about 750 lines of src code. It could certainly be expanded to extract the variable name under more circumstances, but I had to draw a line somewhere.

Note also that it's quite hard to avoid false positives. For example, for an empty array @a, in $a[0] + $a[1] at the time of execution of the addition, both args are the same special address &PL_sv_undef, so its not possible to determine whether a particular undef value came from the LHS or the RHS.

Dave.

In reply to Re: RFC: Adding variable name to warning "Use of uninitialized value ??? in ..." by dave_the_m
in thread RFC: Adding variable name to warning "Use of uninitialized value ??? in ..." by LanX

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