Re^4: What could make "()" a good value for boolean false?

…Maybe this is what is meant?

perl -le 'sub bingo { return 0 }; @a = bingo(); print @a ? "True" : "F
+alse"'
True
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Comment on Re^4: What could make "()" a good value for boolean false? Download Code

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Re^5: What could make "()" a good value for boolean false? by Anonymous Monk on Mar 31, 2016 at 07:54 UTC
Yes (although strictly speaking, that's an array in scalar context), and also `$ perl -wMstrict -le 'sub foo { print wantarray?"list":"scalar"; return 0; }; print( (()=foo()) ? "true" : "false" );' list true` [download] (although strictly speaking, that's a list assignment in scalar context). But there's also perlsyn (emphasis mine): The number 0, the strings '0' and "", the empty list (), and undef are all false in a boolean context. All other values are true.	[reply] [d/l]
Re^6: What could make "()" a good value for boolean false? by ikegami (Patriarch) on Apr 01, 2016 at 15:55 UTC
That doesn't check if `()` is true or false. Change it to `($x)` or `@a` and you'll get exactly the same result. That check if `=` is true or false, which check the number of elements on the RHS of `=`. That passage is poorly worded, leading to people like you quoting it as it says something other than it says. When it says `()`, when it says "`()`", it's actually referring to "the value returned by `()` in scalar context, which is the same thing as saying undef. `()` is not a value. It shouldn't list one of the many many operator that can return something false in scalar context.	[reply] [d/l] [select]