Apologies if this has already been raised - I did look in SuperSearch. Strange behaviour (bug?) of use strict 'subs' (was: ... strict 'vars') dances around it.

Documentation for strict 'subs' states: ... generating a compile-time error if you try to use a bareword identifier that's not a subroutine, unless it ... appears in curly braces...

This does not appear to be the case for keys in a hash slice. For example:
use warnings;
use strict 'subs';

my %hash = qw (k1 v1 k2 v2 k3 v3);

$hash{k1} = 42;                  # is fine
@hash{k1,k2,k3} = (1,2,3);       # BANG! Bareword "k1" not allowed...
@hash{qw(k1 k2 k3)} = (1,2,3);   # is fine

[download]
(Windows ActiveState 5.10.1)
Why are single keys and multiple keys handled differently?

OK, so a hash slice uses a list instead of a scalar, but why should that make a difference? Is an unquoted list somehow more dangerous than an unquoted scalar value?

In reply to Unquoted hash slice keys with use strict 'subs' by cdarke

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