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It is indeed a bit weird since ?: has higher precedence than =

If it were any different, the useful idiom

my $x = $condition ? $a : $b;

would be parsed as

(my $x = $condition) ? $a : $b

which totally wouldn't make sense. It's useful to optimize the operator precedence level for idiomatic use, not for misunderstood corner cases.

That said, it is possible to both allow the common case and detect the error; that's what Perl 6 does:

# program (note that Perl 6 uses ??!! instead of ?:) 1 ?? $_ = 3 !! $_ = 5 # output from the Perl 6 standard grammar: Precedence of = is too loose to use between ?? and !!; please use pare +ns around inner expression at ...

But I guess Perl 5 won't do it soon, because it'll break some obfuscations that successfully "use" that feature somewhere.


In reply to Re^2: Surprised by Perl parse of ternary operator by moritz
in thread Surprised by Perl parse of ternary operator by eyepopslikeamosquito

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    [Discipulus]: you so kid to greet non people..;=)
    Discipulus kind not kid..
    [Corion]: The bots bow in response
    [Discipulus]: so karlgoethebier, what this idiom is and where i can read about it? i tried to deparse and gives error..;=(
    [karlgoethebier]: Eily: non-people == persone non grata?
    [Your Mother]: Corion: I have lost the link to the pmdev guide(s). Do you have that handy?
    [karlgoethebier]: Discipulus: see per lop please how to avoid the classic <c>perl dangerous.pl 'rm -rfv *|'</>
    [Eily]: karlgoethebier: more like grata non persona :P

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