Help with facade pattern

[Daniel Berger]

Hi all,

Well, I *think* it's the facade pattern. Anyway, I'm trying to do
something like this:

class Foo < String
def method_a
Bar.method_a(self)
end
def method_b
Bar.method_b(self)
end
end

This is easy enough to do by hand for a few methods, but what if I have
many methods from Bar I want to use?

I thought maybe there was a trick with Forwardable I could use, but I
don't see how. Any ideas on how to shortcut this?

Regards,

Dan

 

[ES]

Hi all,

Well, I *think* it's the facade pattern. Anyway, I'm trying to do
something like this:

class Foo < String
def method_a
Bar.method_a(self)
end
def method_b
Bar.method_b(self)
end
end

This is easy enough to do by hand for a few methods, but what if I have
many methods from Bar I want to use?

I thought maybe there was a trick with Forwardable I could use, but I
don't see how. Any ideas on how to shortcut this?

You left too quick You are looking at something like this:

class Class
def forward(mod, *methods)
methods.each do |method|
# Substitute mod with const_get(mod) if you want to use :ModName
define_method(method) {|| mod.send(method, self)}
end
end
end

class A
def A.foo(x)
puts "A.foo: #{x}"
end
end

class B
forward A, :foo
end

B.new.foo # => A.foo

Regards,

Dan

E

 

[Daniel Berger]

You left too quick You are looking at something like this:

class Class
def forward(mod, *methods)
methods.each do |method|
# Substitute mod with const_get(mod) if you want to use :ModName
define_method(method) {|| mod.send(method, self)}
end
end
end

class A
def A.foo(x)
puts "A.foo: #{x}"
end
end

class B
forward A, :foo
end

B.new.foo # => A.foo


E

Thank you - that will work beautfully.

Regards,

Dan