Re^5: 'xor' operator is not a sibling to 'or' and 'and'?

It's further down under the heading "Logical Defined-Or" (so yes, it's disjoint from the other discussion of && above it):

    The "||", "//" and "&&" operators return the last value evaluated 
+(unlike
    C's "||" and "&&", which return 0 or 1). Thus, a reasonably portab
+le way
    to find out the home directory might be:
[download]

The cake is a lie.
The cake is a lie.
The cake is a lie.

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Re^6: 'xor' operator is not a sibling to 'or' and 'and'? by rsFalse (Chaplain) on Dec 18, 2019 at 21:35 UTC
Hm, paragraphs about '`\|\|,//,&&`' and about '`and/or/xor`' are distant in docs, because their precedence differs. But also sentences about return values of 'and' and 'or' seems to be incorrect. I think that section needs to be slightly rewritten, with emphasis that 'and' and 'or' do not return logical result, but return evaluated expressions.	[reply] [d/l] [select]
Re^7: 'xor' operator is not a sibling to 'or' and 'and'? by pryrt (Abbot) on Dec 18, 2019 at 22:57 UTC
Stop thinking in terms of bitwise; this is Boolean. The "evaluated expressions" are logical values. 2 is logic-true, 3 is logic-true, 2 and 3 returns 3, which is logic-true. It uses the last evaluated expression as the logical value. C:\usr\local\share\PassThru\perl>perl -le "print +('george' and 'graci +e')" gracie C:\usr\local\share\PassThru\perl>perl -le "print +('0' and 'gracie')" 0 C:\usr\local\share\PassThru\perl>perl -le "print +('' and 'gracie')" C:\usr\local\share\PassThru\perl>perl -le "print +('george' and 'false +')" false C:\usr\local\share\PassThru\perl>perl -le "print +('george' and '')" C:\usr\local\share\PassThru\perl>perl -le "print +(2 and 4)" 4 C:\usr\local\share\PassThru\perl>perl -le "print +(2 && 4)" 4 C:\usr\local\share\PassThru\perl>perl -le "print +(2 & 4)" 0 [download]	[reply] [d/l]
Re^8: 'xor' operator is not a sibling to 'or' and 'and'? by rsFalse (Chaplain) on Dec 18, 2019 at 23:13 UTC
>> Stop thinking in terms of bitwise; this is Boolean. If this is Boolean, shouldn't it return 1 or ''/0? p.s. I haven't write anything about bitwise.	[reply]
Re^9: 'xor' operator is not a sibling to 'or' and 'and'? by pryrt (Abbot) on Dec 19, 2019 at 14:08 UTC
Re^7: 'xor' operator is not a sibling to 'or' and 'and'? by LanX (Saint) on Dec 21, 2019 at 19:31 UTC
> I think that section needs to be slightly rewritten I agree that `&&` and `\|\|` should be extended with the notion: "returns last evaluated side". Probably with an analogous `if` statement. `A \|\| B := do { if (A) {A} else {B} }` I disagree that they "do not return logical result" , because the truth table is fully respected. I don't think the docs to `and/or` need to be extend, because their low precedence and use for flow control makes the use of return values unlikely without brackets. Mentioning the similarity to `&&` and `\|\|` should be sufficient. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply] [d/l] [select]


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