in reply to Re^3: Perl 6, defining a hash with interpolated string
in thread Perl 6, defining a hash with interpolated string

I noticed playing with this code that the output of .perl differs depending on if the colon is in front of the variable:

say :%kv4.perl; #"kv1" => {"LiteralKey" => "LiteralValue"}
say %kv4.perl;  #{"LiteralKey" => "LiteralValue"}

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the colon seems to be plucking the Hash's name and creating a Pair with it.

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Re^5: Perl 6, defining a hash with interpolated string
by molecules (Monk) on Aug 05, 2010 at 11:53 UTC
    Yes that is correct. 
    my $name='Larry';
my $pair = :$name;
say $pair.perl;

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    Outputs: 
    "name" => "Larry"

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    UPDATE:
    This is especially useful for named parameters in subroutine declarations.

    For example: 
    use v6;

foo(  B => 'there',A => 'howdy');

sub foo(Str :$A, Str :$B){
        say "Named parameter A is '$A'";
        say "Named parameter B is '$B'";

}

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      Thanks, that clears a lot up!
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        Or to be even more concise, use the notation you showed earlier: 
        use v6;

foo( :B<there>, :A<howdy> );

sub foo(Str :$A, Str :$B){
        say "Named parameter A is '$A'";
        say "Named parameter B is '$B'";

}

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