@stuff = "This","That","Other";
When I first saw this and other, similar code fragments in this thread, my first expectation was that the comma expression "This","That","Other" would evaluate to the right-most list item, "Other". After all, that's the rule: Evaluate left side, throw away, return right side in left-associative fashion.
After a bit of thought, I realized that the rule is to evaluate the leftmost expression, toss the result, evaluate and return the result of the rightmost expression, left-associative. Of course, the leftmost expression has a side effect: it creates and initializes the @stuff array. The following helped me elucidate the process:
>perl -wMstrict -MO=Deparse,-p -le
"my @stuff = 'One', 'Two', 'Three';
print qq{(@stuff)};
;;
my @stoff = scalar('Eine', 'Zwei', 'Drei');
print qq{(@stoff)};
;;
my @sniff = scalar(my @snarf = '111', '222', '333');
print qq{sniff: (@sniff) snarf: (@snarf)};
;;
my @stiff = ('Uno', 'Dos', 'Tres');
print qq{(@stiff)};
"
Useless use of a constant (Eine) in void context at -e line 1.
Useless use of a constant (Zwei) in void context at -e line 1.
Useless use of a constant (222) in void context at -e line 1.
Useless use of a constant (Two) in void context at -e line 1.
Useless use of a constant (Three) in void context at -e line 1.
BEGIN { $^W = 1; }
BEGIN { $/ = "\n"; $\ = "\n"; }
use strict 'refs';
((my(@stuff) = 'One'), '???', '???');
print("(@stuff)");
(my(@stoff) = scalar(('???', '???', 'Drei')));
print("(@stoff)");
(my(@sniff) = scalar(((my(@snarf) = '111'), '???', '333')));
print("sniff: (@sniff) snarf: (@snarf)");
(my(@stiff) = ('Uno', 'Dos', 'Tres'));
print("(@stiff)");
-e syntax OK
>perl -wMstrict -le
"my @stuff = 'One', 'Two', 'Three';
print qq{(@stuff)};
;;
my @stoff = scalar('Eine', 'Zwei', 'Drei');
print qq{(@stoff)};
;;
my @sniff = scalar(my @snarf = '111', '222', '333');
print qq{sniff: (@sniff) snarf: (@snarf)};
;;
my @stiff = ('Uno', 'Dos', 'Tres');
print qq{(@stiff)};
"
Useless use of a constant (Eine) in void context at -e line 1.
Useless use of a constant (Zwei) in void context at -e line 1.
Useless use of a constant (222) in void context at -e line 1.
Useless use of a constant (Two) in void context at -e line 1.
Useless use of a constant (Three) in void context at -e line 1.
(One)
(Drei)
sniff: (333) snarf: (111)
(Uno Dos Tres)
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