Implement references
Dandigit opened this issue · 1 comments
Dandigit commented
I'd now like to implement references, as in the following:
const x = 2
// Create references with &
const ref = &x
// Dereferencing is automatic
print(ref + 3) // 5
var y = 3
// Create variable references with &var
var yref = &var y
yref = 2
// You cannot reference a reference
const refref = &&x // Error!
// ...Or an rvalue
const rvref = &2 // Error!
// Reference types: &T/&var T
fun add(a int, b int, target &var int):
target = a + b
end
// Subscripting a variable array returns a variable reference
var arr = [1, 2, 3, 4, 5]
arr[0] = 2 // arr = [2, 2, 3, 4, 5]
// Unless the array is const, of course
const carr = [1, 2, 3, 4, 5]
carr[0] = 2 // Error: Cannot assign to a const reference!
// Same applies for variable structs
struct Person:
name string
age int
end
var jim = Person("Jim", 99)
// Accessing a struct member returns a reference
jim.age = 98
// Unless the struct is const, of course
const sam = Person("Sam", 42)
sam.age = 43 // Error: Cannot assign to a const reference!
// Variable references are implicitly convertible to const references, but not the other way around
fun printPerson(person &Person):
print("Person("+person.name", "+string(person.age)+")")
end
printPerson(&var jim) // Works, but could be confusing
printPerson(&jim) // Better
fun jimmifyPerson(person &var Person):
person.name = "Jim"
person.age = 99
end
jimmifyPerson(&sam) // Cannot do this!