On Wed, Jun 5, 2013 at 11:22 PM, MZMcBride z@mzmcbride.com wrote:
The debug console seems finicky. Its line numbers never seem to make sense.
The debug console probably could use some work. The way it works now, it takes your past and current input, plugs all that into some boilerplate to make a function, and then executes that function. The line numbers reported for "Lua error in console input" therefore depend on this boilerplate and on the lines you've previously entered in the session.
It's also possible to break that boilerplate function, as you've seen below.
For example, I input this into a fresh console:
function p.asc(frame) return frame.args[1] end
Then I try ...
= print(p.asc()) Lua error in console input at line 6: attempt to index local 'frame' (a nil value).
I have no idea what line 6 refers to. Earlier when I was testing it was saying line 14.
It's referring to which line in that boilerplate function the "return frame.args[1]" ended up at. Yes, that's not extremely helpful.
If I paste this into the console:
[SNIP]
return p
I get "Lua error in console input at line 18: 'end' expected (to close 'function' at line 1) near 'return'."
This is an example of breaking the boilerplate function. In Lua, it's an error to have unreachable code after a return statement. When you put "return p" into the debug console like that, the boilerplate function winds up looking something like this:
function ( p ) local print = mw.log -- Previous lines go here mw.clearLogBuffer() return p -- This is the line you entered return nil, mw.getLogBuffer() -- This is boilerplate end
Again, the console should probably be made more robust at some point to avoid this sort of thing.
There's a note on the edit screen about using mw.log(), but with various inputs, I still can't seem to get anything working properly with the debug console. For example:
function p.asc(frame) t = {} t['bar'] = 'baz' mw.log(t) return frame.args[1] end
This prints nothing at all when pasted into the debug console.
That's because you're defining a function but not calling it (yet).
If I try "= print(t)" or "print(t)" I get "nil".
Since 't' is a local variable inside the function, it's not defined outside of it.
Is there a var_dump equivalent for Lua that can be used?
Not yet.