Is it possible to create an attribute that can only be set in the constructor in Moose?

moose, perl

Solution

Isn't that just a read-only attribute? If I write

package Foo;
use Moose;

has 'file' => (is => 'ro', isa => 'Str');
has 'string' => (is => 'rw', isa => 'Str');

1;

then your code dies with

Cannot assign a value to a read-only accessor

Problem

Is it possible to create an attribute that can only be set in the constructor in Moose? I’d like to do something like this: ``` my $foo = new Foo(file => 'foo.txt'); my $bar = new Foo(string => $str); $foo->file('baz.txt'); # dies ``` I know I can create an attribute that can not be set in constructor, but the complementary case seems to be missing.

Original source

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