Module: Anise::Annotative::Variables

Includes:
Anise::Annotations
Defined in:
lib/anise/annotative/variables.rb

Overview

I bet you never imagined Ruby could suport @style annotations. Well, I am here to tell you otherwise.

The VariableAnnotator module allows class instance variable to be used method annotations which attach to the next defined method.

class X
extend Anise::Annotative::Variables

variable_annotator :@doc
variable_annotator :@returns

@doc = "See what I mean?"
@returns = NilClass

def see
  puts "Yes, I see!"
end
end

X.ann(:see, :@doc) #=> "See what I mean?"

This library uses the #method_added callback, so be sure to respect good practices of calling super if you need to override this method.

IMPORTANT!!! This library is an interesting expirement, but it remains to be determined if it makes sense for general use.

Instance Method Summary collapse

Methods included from Anise::Annotations

#ann, #ann!, #annotation_added, #annotations

Instance Method Details

#annotator(iv, &block) ⇒ Object 



58
59
60
61
62
63
64
65
66
67
68
 
# File 'lib/anise/annotative/variables.rb', line 58

def annotator(iv, &block)
  if not iv.to_s.start_with?('@')
    if defined?(super)
      super(iv, &block)
    else
      raise ArgumentError, "not a valid instance variable -- #{iv}"
    end
  else
    variable_annotator(iv, ns, &block)
  end
end

#method_added(sym) ⇒ Object

When a method is added, run all pending annotations.



73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
 
# File 'lib/anise/annotative/variables.rb', line 73

def method_added(sym)
  @_variable_annotations ||= {}
  @_variable_annotations.each do |iv, block|
    if iv.to_s.index('/')
      iv, ns = iv.to_s.split('/')
    else
      ns = :ann
    end
    value = instance_variable_get(iv)
    if block
      block.call(sym, value)
    else
      ann(sym/ns, iv=>value)
    end
    # TODO: can we undefine the instance variable?
    instance_variable_set(iv, nil)
  end
  super(sym) if defined?(super)
end

#variable_annotator(iv, &block) ⇒ Object

Open method annotations.

Examples:

variable_annotator :@doc

Parameters:

  • ns (Symbol) —

    Annotator to use. Default is :ann.



46
47
48
49
50
51
52
53
54
55
 
# File 'lib/anise/annotative/variables.rb', line 46

def variable_annotator(iv, &block)
  # TODO: should none iv raise an error instead?
  iv = "@#{iv}".to_sym if iv.to_s !~ /^@/

  # TODO: use an annotation to record the annotators
  #ann(:variable_annotator, iv=>block)

  @_variable_annotations ||= {}
  @_variable_annotations[iv] = block
end