Well, technically, that's exactly what needs to be fixed, but it'd be hard to fix it. The dereferencing operator at the tail end knows if it's in an lvalue (being assigned to) or rvalue (being accessed) context, but apparently, the information is not available to the dereferencing operators in the middle of the chain, and that'd be messy to add. Apparently, it requires adding a new bytecode to Perl, and that has a lot of potential for breaking many more things than it fixes.

For now, the known workaround is to step carefully down the tree, calling exists at each level before proceeding to the next. In practice, I've not been bitten by this, but maybe it's because I had been bitten once or twice while practicing with references. {grin}

-- Randal L. Schwartz, Perl hacker

In reply to Re: Re: Re: exists() unexpected behavior by merlyn
in thread exists() unexpected behavior by Richard

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