Just when I thought I had seen everything: 
my %hash;
my $foo = 'hello';
my $bar = 'world';
my $baz = 'folk';
$hash{ $foo, $bar, $baz } = '##eek what magic is this?';
print $hash{"$foo\x{1c}$bar\x{1c}$baz"};

[download]
##eek what magic is this?

By what rule are multiple variables, separated by a comma, turned into a string with a File Separator between the pieces? I mean if I squint hard enough, that expression for the key is a list, and then the list is "stringified" to be a key, in which case I would have expected a space (\x{20}) separated expression. Perl 5.16 and Perl 5.26.1

In reply to Hash key composition with a comma? by mpersico

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