What about functions with arguments?

Consider the following piece of code:

    fn main() 
    { 
        let a = 32; 
        let b = &a; 
    } 

We have created two variable bindings, with the second one (b) pointing at the address for a. The b variable doesn't contain the value of the a variable, but it points to the position a is held at, from which it can obtain a value (in other words, the value of b is borrowed from a).

In terms of our stack diagram, we have this:

Function name	Address	Variable name	Value
main	1	b	→ address 0
	0	a	32

If we have a function call another function, but with a parameter, our stack will look slightly different:

    fn second(i: &i32) 
    { 
        let c = 42; 
        println!("{}", *i); 
    } 
 
    fn main()  
    { 
        let a = 32; 
        let b = &a; 
        second(b); 
    } 
 

Function name	Address	Variable name	Value
	3	c	42
second	2	i	→ address 0
	1	b	→ address 0
main	0	a	32

 

The i binding points to address 0 and the b variable points to address 0, and this is the...