Suppose there's the following class
# derp.rb
class Derp < Struct.new :id
end
When I load "./derp.rb"
twice the program fails with TypeError: superclass mismatch for class Derp
. Ok, this could be managed with require
. But how can I reload such classes for each test run with Spork? require
obviously won't work cause it caches the loaded files.
Struct.new
is creating new class for your every load.
irb(main):001:0> class Test1 < Struct.new :id; end
nil
irb(main):003:0> class Test1 < Struct.new :id; end
TypeError: superclass mismatch for class Test1
from (irb):3
from /usr/bin/irb:12:in `<main>'
You can save your Struct.new
returned class
to a variable and you
can use that will be always the same class
.
irb(main):004:0> Id = Struct.new :id
#<Class:0x00000002c35b20>
irb(main):005:0> class Test2 < Id; end
nil
irb(main):006:0> class Test2 < Id; end
nil
or You can use Struct.new
block style instead of class
keyword it
will only give warning: already initialized constant Test3
when you
reload your file.
irb(main):023:0> Test3 = Struct.new(:id) do
def my_methods
"this is a method"
end
end
You can make sure the struct class is created only once.
Test1 < $test1 ||= Struct.new(:id)
For those finding this on Google, this is what solved it for me:
module MyModule
class MyClass
MyClassStruct ||= Struct.new(:id)
SomeStruct < MyClassStruct
...
end
end
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