NeuronCheck

Add user keywords

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  NeuronCheck has a simple plug-in mechanism, and users can add original keywords for declaration in addition to built-in keywords.

  For example, if you want to add the new keyword boolean, please describe in the following manner.

  require 'neuroncheck'
  
  NeuronCheckSystem::Plugin.add_keyword(:boolean) do
    # Method that is called when you use the keyword
    # if it is called a keyword in with arguments like `respondable(:each)`, is it also passed as an argument to the on_call method
    def on_call
    end
  
    # Method to perform the actual check processing. There is a need to return either true or false
    def match?(value)
      value.equal?(true) or value.equal?(false)
    end
  
    # String that represents the contents of the keyword. It is used in the error message
    def expected_caption
      "boolean value"
    end
  end
  

  Among the NeuronCheckSystem::Plugin.add_keyword block, like a normal class definition of Ruby, you can define a method. Then, by defining the above-mentioned three methods in which you can define the operation of the keyword.

  Keyword registered in the manner described above, it is possible to use in the same way as other keywords in the ndecl block.

  module Foo
    extend NeuronCheck
    ndecl {
      args boolean
    }
    def self.foo_func(flag: false)
    end
  end
  
  
  Foo.foo_func
  Foo.foo_func(flag: 'invalid')
  #=> script.rb:30:in `<main>': argument `flag' of `Foo.foo_func' must be boolean value, but was "invalid" (NeuronCheckError)
  #             got: "invalid"
  #       signature: Foo.foo_func(flag:boolean value)
  #     declared at: script.rb:22:in `block in <module:Foo>'
  #   
  

  Built-in keywords such as respondable, any and except have been defined by using the plug-in mechanism. (However, there is also a place where you are using the method is not described in the above) If you want to see the contents of the implementation, please refer to the source file neuroncheck/builtin_keyword.rb.

  It should be noted that, in addition to the NeuronCheckSystem::Plugin.add_keyword, It can also be used two methods below.

  require 'neuroncheck'
  
  # As a `boolean` keyword of aliases, define a new `bool` keyword
  NeuronCheckSystem::Plugin.alias_keyword(:bool, :boolean)
  # To remove a `boolean` keyword previously defined
  NeuronCheckSystem::Plugin.remove_keyword(:boolean)