On 10/07/2009 15:31, Peter Hercek wrote:
Hi,
It would be cool if ghci debugger could grab not only the free variables in the selected expression but in one case a bit more. The case is when we stop at a function definition the first time (when just entering it). In this case it should provide bindings of the function arguments. Is it doable without bad consequences? Looks to me like it should not result in some memory leak problems though I do not have idea whether it is hard to do.
The problem is that functions can be defined with multiple equations, each giving different names for the arguments. e.g. in f x 0 = x f 0 x = x when we stop at f, what do you want to see? I think the current policy is to stop at the outer level (no bindings), and the next breakpoint is on the right-hand side of the equation taken, with the appropriate free variables bound. I suppose you could use a scheme whereby the bindings are named if there is only one equation, or otherwise use "_arg1" "_arg2", etc. Cheers, Simon