Defining class methods with Modularity traits

Posted About 13 years ago. Visible to the public. Repeats.

There are two ways to define a class method from a Modularity Show archive.org snapshot trait. Note that the usual caveats regarding class method visibility apply.

Using define_method

The recommended way is to define a method on your module's singleton class:

module SomeTrait
  as_trait do
    define_singleton_method :foo do
      # ...
    end
  end
end

Using def (has caveats!)

Alternatively, you can def the method on self:

module SomeTrait
  as_trait do
    def self.foo
      # ...
    end
  end
end

This is quite concise and results in faster methods than using define_method. However, you cannot use it with parametrized traits.

The following will fail:

module SomeTrait
  as_trait do |name|
    def self.foo
      puts name # will raise an error because the variable 'name' is not bound to the method body
    end
  end
end
Henning Koch
makandra.com
Say thanks
Last edit
Over 1 year ago
Henning Koch
Keywords
static, method
License
Source code in this card is licensed under the MIT License.

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Posted by Henning Koch to makandra dev (2011-03-08 18:48)
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