Let's say I have a list of @objects interspersed with scalar values, and I want to get a list of unique stringified values of all @objects. Each $object has "" operator overloaded so naturally I try to do the intuitive thing:

my @objects = ();
my %unique  = map { "$_" => 1 } @objects;
print sort keys %unique;

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Contrary to my expectation, the construct above produces compiler error:

Not enough arguments for map at test.pl line 2, near "} @objects"
syntax error at test.pl line 2, near "} @objects"
Execution of test.pl aborted due to compilation errors.

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Changing the offending line to...

my %unique  = map { ''.$_ => 1 } @objects;

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...resolves the error. But still there's something I can't understand about it. Why the more natural-looking construct is erroneous, while less intuitive works as expected? Is that another compiler quirk I just have to live with?

Regards,
Alex.

In reply to Strange compiler behavior with map? by dwalin

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