exercises/exercises/040_pointers2.zig
2023-04-05 16:11:56 +02:00

29 lines
802 B
Zig

//
// It's important to note that variable pointers and constant pointers
// are different types.
//
// Given:
//
// var foo: u8 = 5;
// const bar: u8 = 5;
//
// Then:
//
// &foo is of type "*u8"
// &bar is of type "*const u8"
//
// You can always make a const pointer to a mutable value (var), but
// you cannot make a var pointer to an immutable value (const).
// This sounds like a logic puzzle, but it just means that once data
// is declared immutable, you can't coerce it to a mutable type.
// Think of mutable data as being volatile or even dangerous. Zig
// always lets you be "more safe" and never "less safe."
//
const std = @import("std");
pub fn main() void {
const a: u8 = 12;
const b: *u8 = &a; // fix this!
std.debug.print("a: {}, b: {}\n", .{ a, b.* });
}