I am trying to create an automatic 'debugger' for tracing function flow. Because I'm not a god, I do make mistakes, and when I do, I normally end up throwing a bunch of "show" in my functions. What I'm looking to do is create a function that will insert shows prior to each line for each variable used in an expression on that line and any variable assigned to in the previous.
Imagine I have a function f that is throwing an unhelpful error. I would insert f: debugwrap[f]; after the function definition to insert the appropriate debugging within the lines of function string, parse, and return the augmented function.
I have had success handling the params and simple functions, but where I have trouble is where semicolons do not indicate eol, such as in function calls. Using parse on the function body, I can easily break out all the lines and find the required variables, but once I do that, I need to 'unparse' each line in the function. That unparsing is giving me trouble, especially where functions are translated to what I believe is k - such as "*:".
Simple example with only initial logging:
q)f: {[a;b] a: a xexp b; c: a-first `int$-1#string first table[`symbols]; :c }
q)df: dp[f;";"]
q)df
"{[a;b] show "a is ",string[a]; show "b is ",string[b]; a : a xexp b;c : a - *:`int$-1#$:*:table`symbols;: c;}"
q)parse df
ERROR: *:
What I'm doing now is recursively walking through the parse tree and reconstructing the call. That is painful and not yet yielding results. What I think is the best way is to get the information I need out of each parse subtree, then unparse that subtree and append it to my function string.
Appreciate any help you all can offer.
