[project @ 2004-01-23 13:55:28 by simonmar]
Some small steps in the direction of making GHC useable as a library: - The ErrMsg type is now richer: we keep the location info and the PrintUnqualified separate until the message is printed out, and messages have a short summary and "extra info", where the extra info is used for things like the context info in the typechecker (stuff that you don't normally want to see in a more visual setting, where the context is obvious because you're looking at the code). - hscMain now takes an extra argument of type (Messages -> IO ()), which says what to do with the error messages. In normal usage, we just pass ErrUtils.printErrorsAndWarnings, but eg. a development environment will want to do something different. The direction we need to head in is for hscMain to *never* do any output to stdout/stderr except via abstractions like this.