Functions and Updating two values

[EiCCA]

There are two questions I have here in this topic

1) In C++, you can declare a function type as void, meaning it does not return a value. What is the term for this in Turing?

2) I have a situation where I need two variables in a funtion to update their values after the function closes.

For example:

code:

function asdf(x : int, y : int) : <void>        x := 5        y := 6 end asdf put x put y

In C++, you can do this using refrence paramaters, using the & beside the paramater name, however I do not know how this is done in Turing.

Help? Thanks a lot

[wtd]

1. Such things are known as procedures in Turing.

2. You can do this in Turing by prefixing the parameter name with "var ". However, for such a simple case, there is a better approach. Simply link both variables into a single data type, then return that.

code:

type Point :   record     x, y : int   end record

Or in C++ simply use the std::pair class as defined by the STL.

[Tony]

code:

function asdf(x : int, y : int) : <void>        x := 5        y := 6 end asdf put asdf(1,2)

the above clearly doesn't work. X and Y are local variables.

What'd you'd need to do is pass the reference to the variable's address. Now you're getting into pointers and what not. Turing might actually have a similar syntax involving &, but I don't recall at the moment. Consult your F10 manual.

Raguardless, the best practice is to have the function return the updated values.

[[Gandalf]]

Tony, like wtd said you can get the pass by reference effect by prefixing the parameter name with "var", for example:

code:

procedure changeValue (var num : int)     num += 5 end changeValue var myValue : int := 7 put myValue changeValue (myValue) put myValue %outputs 12

Though yes, you could also return a type containing all your data.

[Tony]

ah. thx for pointing that out.