Re^2: Possible useless use of map

What bug? In:

map {$hr->{stuff}} 1
[download]

there is no hash element in void context. It's in list context.

Comment on Re^2: Possible useless use of map Download Code

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Re^3: Possible useless use of map by Anonymous Monk on Mar 18, 2010 at 14:48 UTC
perl590delta says map in void context is no longer expensive. map is now context aware, and will not construct a list if called in void context. if there is no list, why is there list context?	[reply]
Re^4: Possible useless use of map by JavaFan (Canon) on Mar 18, 2010 at 15:04 UTC
Just like about any other operator in Perl, `map` imposes a certain context on its operands, regardless of the context it itself is in. In: `map {$hash->{foo}} 1;` [download] there are actually two lists, both containing a single element: the first list consists of `$hash->{foo}`, the second of `1`. Think of it this way, if `map` would not provide list context to its inner block, the following wouldn't do what it does now: `%h = map {$_ => 1} qw[foo bar baz];` [download]	[reply] [d/l] [select]