Re^4: Logical/defined or as lvalue

... implementing the "Elvis operator" ... as $x ? $x : $y

Actually, I read the opposite from the Wiki article:

... the Elvis operator expression A ?: B is approximately equivalent to the ternary conditional expression A ? A : B

... something like ... x = f() ?: g() ... is equivalent to ... the conditional ternary operator x = f() ? f() : g() except that it does not evaluate f() twice if it yields truthy.

Accentuations by me.

Greetings,
🐻

$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$

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Re^5: Logical/defined or as lvalue by ikegami (Patriarch) on Sep 04, 2024 at 17:00 UTC
That makes PHP's Elvis operator a value-preserving logical-OR operator, like Perl's `\|\|`. According to the article, `\|\|` also has this function in Common Lisp, Clojure, Lua, Object Pascal, Python, Ruby, and JavaScript. It's rather disingenuous to call the article "Elvis operator". In C, `\|\|` is normalizes the value to `0` or `1`.	[reply] [d/l] [select]
Re^6: Logical/defined or as lvalue by jo37 (Curate) on Sep 04, 2024 at 18:36 UTC
In retrospective, I shouldn't have brought up `\|\|` as I don't see any use for an lvalue expression `X \|\| Y` neither, which would be equivalent to the "Elvis operator". A possible novelty could be a binary operator that: acts like `defined(X) ? X : Y` yields an lvalue, provided `X` and `Y` are lvalues evaluates `X` only once If `X // Y` was an lvalue, it would satisfy these criteria. As it currently isn't, it could hardly break anything as such usage doesn't compile. No new operator, just an extension. In a Perlish sense: One more way to do it. Greetings, 🐻 `$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$`	[reply] [d/l] [select]
Re^7: Logical/defined or as lvalue by ikegami (Patriarch) on Sep 04, 2024 at 21:05 UTC
Everything I said about `\|\|` also applies to `//`. You only mention backwards-compatibility which wasn't even an issue I raised.	[reply] [d/l] [select]