5
6
7
8
9
10
11
12
13
14
15
16
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
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
# File 'lib/attributes.rb', line 5
def attributes *a, &b
unless a.empty?
hashes, names = a.partition{|x| Hash === x}
names_and_defaults = {}
hashes.each{|h| names_and_defaults.update h}
names.flatten.compact.each{|name| names_and_defaults.update name => nil}
names_and_defaults.each do |name, default|
init = b || lambda { default }
ivar, getter, setter, query, banger =
"@#{ name }", "#{ name }", "#{ name }=", "#{ name }?", "#{ name }!"
raise NameError, "bad instance variable name '#{ ivar }'" if ivar =~ %r/[!?=]$/o
define_method(setter) do |value|
__pervasive__('instance_variable_set', ivar, value)
end
define_method(getter) do |*value|
unless value.empty?
__pervasive__('send', setter, value.shift)
else
defined = __pervasive__('instance_variable_defined?', "#{ ivar }")
__pervasive__('send', setter, __pervasive__('instance_eval', &init)) unless defined
__pervasive__('instance_variable_get', ivar)
end
end
define_method(banger) do
__pervasive__('send', setter, __pervasive__('instance_eval', &init))
__pervasive__('instance_variable_get', ivar)
end
alias_method query, getter
(attributes << name.to_s).uniq!
attributes
end
else
begin
__attribute_list__
rescue NameError
singleton_class =
class << self
self
end
klass = self
singleton_class.module_eval do
attribute_list = []
define_method('attribute_list'){ klass == self ? attribute_list : raise(NameError) }
alias_method '__attribute_list__', 'attribute_list'
end
__attribute_list__
end
end
end
|