Class: Module

Inherits:
Object show all
Includes:
Og::MetaLanguage
Defined in:
lib/og/meta.rb,
lib/glue/property.rb,
lib/glue/attribute.rb

Overview

– Extends the module object with module and instance accessors for class attributes, just like the native attr* accessors for instance attributes. Aliases for classes are also provided.

Example:

mattr_accessor :my_attr, ‘Default value’ ++

Instance Method Summary collapse

Methods included from Og::MetaLanguage

#belongs_to, #has_many, #has_one, #joins, #many_to_many, #refers_to, #sql_index

Instance Method Details

#mattr_accessor(*syms) ⇒ Object Also known as: cattr_accessor 



77
78
79
80
 
# File 'lib/glue/attribute.rb', line 77

def mattr_accessor(*syms)
  mattr_reader(*syms)
  mattr_writer(*syms)
end

#mattr_reader(*params) ⇒ Object Also known as: cattr_reader

:nodoc:



17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
 
# File 'lib/glue/attribute.rb', line 17

def mattr_reader(*params)
default = if params.last.is_a?(Symbol) then nil else params.pop end


  for sym in params
	module_eval <<-"end_eval", __FILE__, __LINE__
	
      if not defined?(@@#{sym.id2name})
        @@#{sym.id2name} = #{default.inspect}
      end
      
      def self.#{sym.id2name}
        @@#{sym}
      end

      def #{sym.id2name}
        @@#{sym}
      end

      def call_#{sym.id2name}
        case @@#{sym.id2name}
          when Symbol then send(@@#{sym})
          when Proc   then @@#{sym}.call(self)
          when String then @@#{sym}
          else nil
        end
      end
		
    end_eval
  end
end

#mattr_writer(*params) ⇒ Object 



50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
 
# File 'lib/glue/attribute.rb', line 50

def mattr_writer(*params)
default = if params.last.is_a?(Symbol) then nil else params.pop end

  for sym in params
	module_eval <<-"end_eval", __FILE__, __LINE__

      if not defined?(@@#{sym.id2name})
        @@#{sym.id2name} = #{default.inspect.inspect}
      end
      
      def self.#{sym.id2name}=(obj)
        @@#{sym.id2name} = obj
      end

      def self.set_#{sym.id2name}(obj)
        @@#{sym.id2name} = obj
      end

      def #{sym.id2name}=(obj)
        @@#{sym} = obj
      end

    end_eval
  end
end

#meta(key, val) ⇒ Object

Attach metadata. Guard against duplicates, no need to keep order. This method uses closures :) – gmosx: crappy implementation, recode. ++



378
379
380
381
382
383
384
 
# File 'lib/glue/property.rb', line 378

def meta(key, val)
	self.module_eval %{  
		@@__meta[key] ||= [] 
		@@__meta[key].delete_if { |v| val == v }
		@@__meta[key] << val			
	}
end

#prop(*params) ⇒ Object

Define a property (== typed attribute) This works like Ruby’s standard attr method, ie creates only one property.

Use the prop_reader, prop_writer, prop_accessor methods for multiple properties.

Examples: prop String, :name, :sql => “char(32), :sql_index => ”name(32)“ –> creates only writer. prop Fixnum, :oid, writer = true, :sql => ”integer PRIMARY KEY“ –> creates reader and writer.



260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
 
# File 'lib/glue/property.rb', line 260

def prop(*params)
	meta, klass, symbols = N::PropertyUtils.resolve_prop_params(params) 	
	symbol = symbols.first
	
	N::PropertyUtils.enchant(self)

	if self.is_a?(Class)

		# Add some extra code to append features to 
		# subclasses.

		self.module_eval %{ 
			def self.inherited(sub)
				N::PropertyUtils.enchant(sub)
				N::PropertyUtils.copy_props(self, sub)
				# gmosx: We have to define @@__props first to avoid reusing
				# the hash from the module. super must stay at the end.
				super
			end
		}
	else

		# Add some extra code for modules to append
		# their features to classes that include it.
		
		self.module_eval %{ 
			def self.append_features(base)
				N::PropertyUtils.enchant(base)
				N::PropertyUtils.copy_props(self, base)

				# gmosx: We have to define @@__props first to avoid reusing
				# the hash from the module. super must stay at the end.
		
				N::PropertyUtils.include_meta_mixins(base)
				
				super
			end
		}
	end
	
	property = N::Property.new(symbol, klass, meta)
	
	reader = meta[:reader] || true
	writer = writer || meta[:writer] || false

	meta[:reader] = true if meta[:reader].nil?
	if defined?(writer)
		meta[:writer] = writer 
	else
		meta[:writer] = true if meta[:writer].nil?
	end

	N::PropertyUtils.add_prop(self, property)

	# gmosx: should be placed AFTER enchant!
	
	N::PropertyUtils.include_meta_mixins(self)
end

#prop_accessor(*params) ⇒ Object

Helper method. Accepts a collection of symbols and generates properties. Generates reader and writer.

Example: prop_accessor String, :name, :title, :body, :sql => “char(32)”



359
360
361
362
363
364
365
366
367
368
 
# File 'lib/glue/property.rb', line 359

def prop_accessor(*params)
	meta, klass, symbols = N::PropertyUtils.resolve_prop_params(params) 	

	meta[:reader] = true
	meta[:writer] = true
	
	for symbol in symbols
		prop(klass, symbol, meta)
	end
end

#prop_reader(*params) ⇒ Object

Helper method. Accepts a collection of symbols and generates properties. Only generates reader.

Example: prop_reader String, :name, :title, :body, :sql => “char(32)”



325
326
327
328
329
330
331
332
333
334
 
# File 'lib/glue/property.rb', line 325

def prop_reader(*params)
	meta, klass, symbols = N::PropertyUtils.resolve_prop_params(params) 	
	
	meta[:reader] = true
	meta[:writer] = false
	
	for symbol in symbols
		prop(klass, symbol, meta)
	end
end

#prop_writer(*params) ⇒ Object

Helper method. Accepts a collection of symbols and generates properties. Only generates writer.

Example: prop_writer String, :name, :title, :body, :sql => “char(32)”



342
343
344
345
346
347
348
349
350
351
 
# File 'lib/glue/property.rb', line 342

def prop_writer(*params)
	meta, klass, symbols = N::PropertyUtils.resolve_prop_params(params) 	

	meta[:reader] = false
	meta[:writer] = true
	
	for symbol in symbols
		prop(klass, symbol, meta)
	end
end