Too many declarations of “+” match this call – When Compilers lie

A compiler is often your best friend as a programmer. It will helpfully point out the fact that you may have made a typo, or are about to do something silly. Most of the time, it’ll even helpfully point out where exactly you’ve not quite got it spot on.
But, like any long-term relationship, the Programmer and the Compiler do have the occasional falling out. This happens especially when the compiler becomes recalcitrant, uncommunicative, cryptic, or just flat out lies to you.

Being primarily a PL/SQL programmer my particular relationship is with the ADA pre-compiler that lives inside Oracle. Her name is DIANA.
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