From: kwatch@... (kwatch)
Date: 2002-03-12T12:57:14+09:00
Subject: [Q] Can I write 'foo.bar[key] = value' ?

Hi, 
If you have a good idea, please tell me.

I defined the following class, that works fine.
..________________________________________
class A
    def initialize(val=nil)
        @value = val
    end
    
    def value
        @value
    end
    
    def value=(val)
        @value = val
    end
end


a = A.new(1)
p a.value		# 1
a.value=("abc")
p a.value		# "abc"
..________________________________________


But the following doesn't work (compile error).
..________________________________________

class B
    def initialize
        @values = Hash.new
    end

    def value(key)
        @values[key]
    end

    #def value[]=(key, val)	# parse error
    #def value[key]=(val)	# parse error
    def value=(key, val)	# compile ok
        @value[key] = val
    end
end

b = B.new
b.value=(1, "abc")		# parse error:
			#   b.value=(1, "abc")
			#              ^
..________________________________________


What I want to do is 'b.value[key] = 1'.
Should I write code like this?
..________________________________________
class B
    .....
    def setvalue(key, val)
        @value[key] = val
    end
    ....
end
..________________________________________


I'd like to write 'b.value[key] = 1', like 'a.value = 1'.
If you have a good solution, please teach me.


Regards,
kwatch