id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
2596	Token concatentation (##) in C preprocessor	sedillard		"{{{
#define MY_MACRO(A,B) \
instance MyClass A##B where ...

MY_MACRO(Foo,Bar)
}}}

Should expand to 

{{{
instance MyClass FooBar where ...
}}}

This behavior is defined in the C standard, and is quite handy. Presently GHC leaves the '##' in the expanded text."	feature request	closed	normal		Compiler	6.8.3	invalid			Unknown/Multiple	Unknown/Multiple		Unknown