Be careful when using FUNCT

Hi, you know FUNCT was added to R2.7.7. It defines a function with all set-words as locals. Mostly for us, lazy programmers may be :) I faced a problem when using this function, I had a reasonably big function in a reasonably big object (gui). First I use that function just for its return value so everything was ok. But then I added some code to change some gui vars. It didn't work with NO error ofcourse. It took thirty minutes to find out what it going on, I PROBED everything, everything had a value, so why it didn't work. Then I remembered I used FUNCT. Here is a quick example: b: 1 o: context [ a: 1 f: funct [][a: 2 b: 2] ] o/f o/a == 1 ;not 2 Of course it is easy to see the problem when your object/function is not that big. But when they are getting bigger or if you added some new codes a few months later then you may forget. I have a quick solution, I changed FUNCT color to red using my text editor's syntax highlighting feature :)

Ofcourse you can do this, it will work as expected: o: context [ a: 1 f: funct [][o/a: 2 b: 2] ]

Thank you for the heads up Endo :)

Try this: o: context [ a: 1 f: funct/with [][a: 2 b: 2] self ] That binds the function to the object first and excludes the object's words from the function's locals. When FUNCT/with is passed an object reference the function becomes something like a friend function in C++. When passed a block the function gets a local object to store static words in.

Thank you BrainH, that is great. Here is an example usage: f: funct/with [] [b: b + 1] [b: 1]