id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
393	functions without implementations	c_maeder	simonpj	"{{{
Allow to declare a function by only supplying its type
signature.
This feature shall enhance rapid prototyping by fixing
an interface but leaving some functions unimplemented.

Currently this can be (only) simulated by supplying
dummy implementations, like 

f :: ...
f = undefined

Since it is possible to supply dummy data types by
""data T"" (not followed by ""=""), allowing functions
without implementations seems almost to be a logical
consequence. Surely, the compiler should emit warnings
for missing implementations.

It would be nice if such function declarations via type
signatures could be repeated at any position within a
module. 

}}}"	feature request	new	normal	_|_	Compiler (Type checker)	None	None		tomasz.zielonka@… maeder@… pho@…	Unknown/Multiple	Unknown/Multiple	None/Unknown	Moderate (less than a day)