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On 20/12/14 08:23 PM, Sean Conner wrote:

It was thus said that the Great Soni L. once stated:

On 20/12/14 07:27 PM, Sean Conner wrote:

It was thus said that the Great Soni L. once stated:

So let's say I'm hacking the internals and I wanna force a Lua function
to stop and just return whatever I want instead of continuing and/or
returning what it wants to return. How can I do this?

   Um ... insert a return statement where you want it to return, with the
data you want to return?

   -spc



I want `return Return()` inside a string.gsub to make the string.gsub
return whatever I pass to the Return function. I want to be able to pass
a function as a callback and force the called function to return early.
I want to be able to `x = x and ((x == y and Return()) or (x == z and
a)) or b`. I can't do any of this with a plain return statement.

   Just so I'm clear on this---

	x = string.gsub(data,".",function(c)
		if c:match "%d" then
		  Return("Fools!  There is no answer!")
		else
		  return c:upper()
		end
	end)

   So, if you call

	data = "one two three"
	x = string.gsub( --[[ the above code ]] )

   you get "ONE TWO THREE", but if you call:

	data = "one two 23-skidoo"
	x = string.gsub( --[[ the above code ]] )

   you get "Fools!  There is no answer!"  Is that correct?

   If that's not correct, could you please provide an example.

That is correct for:

	x = string.gsub(data,".",function(c)
		if c:match "%d" then
		  return Return("Fools!  There is no answer!") -- tail call, the stack frame gets replaced, the Return function sees the previous stack frame
		else
		  return c:upper()
		end
	end)



   Also, you might want to look into

	https://github.com/franko/luajit-lang-toolkit

It contains a Lua parser (parses Lua into an AST) in Lua itself, so you
might be able to add whatever extentions you want and test them out.

   -spc (Just a suggestion)




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