[Issue 12461] Typedef and opOpAssign

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=12461

bearophile_hugs at eml.cc changed:

           What    |Removed                     |Added
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                 CC|                            |bearophile_hugs at eml.cc

--- Comment #2 from bearophile_hugs at eml.cc ---
(In reply to Andrej Mitrovic from comment #1)

> But I'm not sure if this is the appropriate fix.
> Do you have a better idea?

In Haskell this doesn't compile (newtype is a built-in that is similar to
Typedef):


newtype T = T Int

main = do
    let a = 10 :: T
    let b = 20 :: T
    let c = a + b :: T
    print c




You have to ask the compiler to activate the arithmetic operations between two
newtypes:


{-# LANGUAGE GeneralizedNewtypeDeriving #-}

newtype T = T Int deriving (Num, Show)

main = do
    let a = 10 :: T
    let b = 20 :: T
    let c = a + b :: T
    print c


And now it prints:

T 30

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