Dynamically generate writer/reader from attribute names in Moose

Question

In Moose we can put restrictions on instance attributes or add getters/setters like so:

has 'color' => (

  is  => 'rw',

  isa => 'Str',

  writer => '_set_color',

);

My question is, is there a way to do this dynamically for an array of elements? It's possible to do something like this:

has ['color', 'temperature', 'size'] => (

  is  => 'rw',

  isa => 'Str',

);

But is there a way to create for each of these items its own writer (or reader), e.g.

_set_color

,

_set_temperature

,

_set_size

? I tried to see if the following yielded any insight, but it returned an error

bad accessor/reader/writer/predicate/clearer format, must be a HASH
ref

has ['color', 'temperature', 'size'] => (

  is  => 'rw',

  isa => 'Str',

  writer => sub {

    print Dumper(\@_);

    return;

);

What I am hoping to get is something like (which doesn't work):

has ['color', 'temperature', 'size'] => (

  is  => 'rw',

  isa => 'Str',

  writer => "_set_$_";

);

I need custom writers, so just going for the ones provided by Moose does not work for me.

Answer 1

has isn't magic. It's just a subroutine call. So something like this should work (untested):

for (qw[colour temperature size]) {
  has $_ => (
    is     => 'rw',
    isa    => 'Str',
    writer => "_set_$_",
  );
}

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