Re^2: can sub check context for lvalue vs rvalue context?

What would your wantlvalue return if called this way: @x = x() = 5;?

I think operator associativity can help answer that one:

$ perl -MO=Deparse -e ' @x = x() = 5; '
@x = (x() = 5);
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So I'd say that x() is ~~primarily~~ in lvalue context here. And what's being assigned to @x is not the return value of x(), but the return value of the assignment operation, which is an lvalue itself.

$ perl -le 'sub x : lvalue { $a } (x() = 4) = 2; print $a'
2
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Re^3: can sub check context for lvalue vs rvalue context? by BrowserUk (Patriarch) on May 09, 2018 at 15:15 UTC
So I'd say that x() is primarily in lvalue context here. That implies it has a secondary context. It doesn't. When an lvalue sub is called, it always does the same thing. Returns an lvalue to the calling context. And what's being assigned to @x is not the return value of x(), but the return value of the assignment operation, which is an lvalue itself. What is assigned to @x, is the result of the rvalue expression. And that, is the result of the assignment to lvalue returned by the subroutine. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity. In the absence of evidence, opinion is indistinguishable from prejudice. Suck that fhit	[reply]
Re^4: can sub check context for lvalue vs rvalue context? by haukex (Archbishop) on May 10, 2018 at 11:20 UTC
That implies it has a secondary context. It doesn't. Yes, of course - I was a little sloppy with my language. And what's being assigned to `@x` is not the return value of `x()`, but the return value of the assignment operation, which is an lvalue itself. What is assigned to @x, is the result of the rvalue expression. And that, is the result of the assignment to lvalue returned by the subroutine. Yes, I think we're both saying the same thing here.	[reply] [d/l] [select]