Class: Command::Argument

Inherits:
Object
  • Object
show all
Defined in:
lib/command-set/arguments.rb

Overview

An Argument has a name and a value. They’re used to to validate input, provide input prompts (like tab-completion or pop-up menus.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, basis = nil) ⇒ Argument

Returns a new instance of Argument.



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# File 'lib/command-set/arguments.rb', line 14

def initialize(name, basis=nil)
  @name = name.to_s
  @basis = basis
end

Instance Attribute Details

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/command-set/arguments.rb', line 19

def name
  @name
end

Class Method Details

.register(shorthand, type = nil) ⇒ Object

Used for new Argument subclasses to register the types they can be based on, and the explicit names of the arguments



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# File 'lib/command-set/arguments.rb', line 10

def self.register(shorthand, type=nil)
  DSL::Argument::register_argument(self, shorthand, type)
end

Instance Method Details

#basis(subject = nil) ⇒ Object 



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# File 'lib/command-set/arguments.rb', line 25

def basis(subject = nil)
  return @basis unless DSL::Argument::SubjectDeferral === @basis
  return @basis.realize(subject)
end

#check_present(keys) ⇒ Object 



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# File 'lib/command-set/arguments.rb', line 73

def check_present(keys)
  unless keys.include?(@name)
    raise OutOfArgumentsException, "Missing argument: #@name!"
  end
end

#complete(original_terms, prefix, subject) ⇒ Object

Provides a list of completion options based on a string prefix and the subject The completion should be an array of completion options. If the completions have a common prefix, completion will enter it for the user. As a clever trick for providing hints:

[ "This is a hint", "" ]

Raises:

  • (NotImplementedError) 


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# File 'lib/command-set/arguments.rb', line 42

def complete(original_terms, prefix, subject)
  raise NotImplementedError, "complete not implemented in #{self.class.name}"
end

#consume(subject, arguments) ⇒ Object

Pulls strings from an ordered list of inputs and provides the parsed data to the host command Returns the parsed data or raises ArgumentInvalidException



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# File 'lib/command-set/arguments.rb', line 54

def consume(subject, arguments)
  term = arguments.shift
  unless validate(term, subject)
  raise ArgumentInvalidException, {@name => term}
  end
  return {@name => term}
end

#consume_hash(subject, hash) ⇒ Object 



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# File 'lib/command-set/arguments.rb', line 62

def consume_hash(subject, hash)
  unless((term = hash[name]).nil?)
    if validate(term, subject)
      return {name => parse(subject, term)}
    else
      raise ArgumentInvalidException, {name => term}
    end
  end
  return {}
end

#match_terms(subject, terms, arguments) ⇒ Object

Used for completion, to skip along terms and arguments until we’re at a place where completion begins. Both the terms and arguments arrays are modified by this method, so a number of clever tricks can be played to make completion work.



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# File 'lib/command-set/arguments.rb', line 83

def match_terms(subject, terms, arguments)
  arguments.shift
  validate(terms.shift, subject)
end

#names ⇒ Object 



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# File 'lib/command-set/arguments.rb', line 21

def names
  return name()
end

#omittable? ⇒ Boolean

Used in completion to recognize that some arguments can be skipped

Returns:

  • (Boolean) 


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# File 'lib/command-set/arguments.rb', line 89

def omittable?
  false
end

#parse(subject, term) ⇒ Object

Returns the parsed data equivalent of the string input



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# File 'lib/command-set/arguments.rb', line 99

def parse(subject, term)
  return term
end

#required? ⇒ Boolean

Used in validation to require some arguments, and allow others to be optional

Returns:

  • (Boolean) 


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# File 'lib/command-set/arguments.rb', line 94

def required?
  true
end

#subject_requirements ⇒ Object 



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# File 'lib/command-set/arguments.rb', line 30

def subject_requirements
  if DSL::Argument::SubjectDeferral === @basis
    return @basis.subject_requirements
  else
    return []
  end
end

#validate(term, subject) ⇒ Object

Validates the input string against the type of the argument. Returns true if the input is valid, or else false

Raises:

  • (NotImplementedError) 


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# File 'lib/command-set/arguments.rb', line 48

def validate(term, subject)
  raise NotImplementedError, "validate not implemented in #{self.class.name}"
end