1
2
3
4
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
|
class Module
# Generates identity/key methods based on specified accessors.
#
# equate_on :a, :b
#
# _is equivalent to_
#
# def ==(o)
# self.a == o.a && self.b == o.b
# end
#
# def eql?(o)
# self.a.eql?(o.a) && self.b.eql?(o.b)
# end
#
# def hash()
# self.a.hash ^ self.b.hash
# end
#
# TO BE DEPRECTED (This was usurped by Equatable.)
def equate_on(*fields)
code = ""
code << "def ==(o) " << fields.map {|f| "self.#{f} == o.#{f}" }.join(" && ") << " end\n"
code << "def eql?(o) " << fields.map {|f| "self.#{f}.eql?(o.#{f})" }.join(" && ") << " end\n"
code << "def hash() " << fields.map {|f| "self.#{f}.hash" }.join(" ^ ") << " end\n"
class_eval( code )
fields
end
# Deprecated.
#alias_method :key_attributes, :equate_on
end
|
