I don't know about Perl 6, but I don't see any reason for the reference judo here. 

my %h = map { chomp; (split /\s+/, $_, 2)[0,1] } <DATA>;
print Dumper \%h;
__DATA__
two 2
one
three 3 X

[download]

Output: 

$VAR1 = { 
          'three' => '3 X',
          'one' => undef,
          'two' => '2'
        };

[download]

But then, I probably also wouldn't use map to loop over a reading filehandle this way either. I don't think the brevity quite justifies reading the whole file before processing.

Update: And if you want to add in default values, another map would make that explicit easier than adding more into the one loop. 

my %h = map { defined ? $_ : $default }
        map { chomp; (split /\s+/, $_, 2)[0,1] } <DATA>;

[download]

In reply to Re: [Perl 6] List of length 2 or... by kyle
in thread [Perl 6] List of length 2 or... by blazar

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