I agree with both of you.

Yes you are never returning a read only value.

But as BUK demonstrated the caller could take a reference* and assign later.

In this case your logic would break without a protecting tie.

Anyway did you benchmark the impact of a tie?

IIRC does a tied variable without FETCH method fall back to a normal read.°

Not sure about the resulting performance penalty.

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Wikisyntax for the Monastery

*) Your WANTLVALUE would need reflect this too, like in an extra state "referenced".

°) looks like I was confusing the semantics of Tie::Scalar (with a fallback method) with a normal perltie on scalars, where FETCH must be defined.

In reply to Re^11: can sub check context for lvalue vs rvalue context? by LanX
in thread can sub check context for lvalue vs rvalue context? by perl-diddler

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