Top level mutable data structures problem

Tomasz Zielonka t.zielonka at
Wed Oct 20 11:54:37 EDT 2004

On Wed, Oct 20, 2004 at 04:38:54PM +0100, Simon Peyton-Jones wrote:
> b) how much happier your life would be if it were implemented

Or... How much sadder your life will be if this mechanism will be
abused and overused. Someone already noticed that with such and
extension main is no longer neccessary. Imagine you have to check all
modules (even those that are only imported, but not used) to understand
what the program is doing. In current situation I can quickly eliminate
some modules from consideration.

I didn't follow the whole discussion, but there was some proposition,
by John Hughes IIRC, to extend the implicit parameter mechanism by
allowing to leave some part of type signature unspecified. This would
help in situations where you want to write the type signatures of
functions, but you would rather like to omit the types of implicit

If it's not clear, I am talking about using implicit parameters to
emulate global variables. This has the benefit that the use of
global variables is controlled, checked by the compiler.

Best regards,

.signature: Too many levels of symbolic links

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