Parentheses needed when declaring a type synonym with ':
Consider the following code:
{-# LANGUAGE DataKinds, TypeOperators #-}
type Foo = (Int ': '[])
type Bar = Int ': '[]
The declaration for Foo
compiles, while the declaration for Bar
fails with a parse error on :
.
This is clearly easy to work around, but I thought it was enough of an infelicity to be reported.
Trac metadata
Trac field | Value |
---|---|
Version | 7.5 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler (Parser) |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |