G'day Hosen1989,

I suspect you may be mixing (and consequently, confusing) this type of Moose syntax: 

has attribute => (
    default => sub { 0 },
);

[download]

with normal Perl syntax for creating key-value pairs: 

{
    default => 0,
}

[download]

sub { 0 } is a code reference.

For your simpler cases, like 

    description => sub{0}

[download]

you could just use 

    description => 0

[download]

However, regardless of the complexity of the code within sub { ... }, what you really want is the return value when that code is executed. For that, use 

sub { ... }->()

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Consider these three one-liners: 

$ perl -wE 'my $x = { y => 0 }; say $x->{y}'
0

[download]
$ perl -wE 'my $x = { y => sub { 0 } }; say $x->{y}'
CODE(0x7f8c34026a60)

[download]
$ perl -wE 'my $x = { y => sub { 0 }->() }; say $x->{y}'
0

[download]

-- Ken

In reply to Re: defined class variable with Moose by kcott
in thread defined class variable with Moose by Hosen1989

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