• simonpj@microsoft.com's avatar
    Undo the fix for Trac #3772 and do it a new way · 9a4c93a5
    simonpj@microsoft.com authored
    The main idea is that I'm now treating a single-method dictionary very
    much like a multi-method dictionary.  In particular, it respond to
    exprIsConApp_maybe, even though newtypes aren't *really* proper
    constructors.
    
    See long comments with Note [Single-method classes] for why
    this slight hack is justified.
    9a4c93a5
TcInstDcls.lhs 50.5 KB