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//
// Passing integer pointers around is generally not something you're going
// to do. Integers are cheap to copy.
//
// But you know what IS useful? Pointers to structs:
//
// const Vertex = struct{ x: u32, y: u32, z: u32 };
//
// var v1 = Vertex{ .x=3, .y=2, .z=5 };
//
// var pv: *Vertex = &v1; // <-- a pointer to our struct
//
// Note that you don't need to dereference the "pv" pointer to access
// the struct's fields:
//
// YES: pv.x
// NO: pv.*.x
//
// We can write functions that take pointer arguments:
//
// fn foo(v: *Vertex) void {
// v.x += 2;
// v.y += 3;
// v.z += 7;
// }
//
// And pass references to them:
//
// foo(&v1);
//
//
// Let's revisit our RPG example and make a printCharacter() function
// that takes a Character pointer.
//
const std = @import("std");
const Class = enum {
wizard,
thief,
bard,
warrior,
};
const Character = struct {
class: Class,
gold: u32,
health: u8 = 100, // <--- You can also provide fields a default value!
experience: u32,
};
pub fn main() void {
var glorp = Character{
.class = Class.wizard,
.gold = 10,
.experience = 20,
};
// FIX ME!
// Please pass our Character "glorp" to printCharacter():
printCharacter(???);
}
// Note how this function's "c" parameter is a pointer to a Character struct.
fn printCharacter(c: *Character) void {
// Here's something you haven't seen before: when switching an enum, you
// don't have to write the full enum name. Zig understands that ".wizard"
// means "Class.wizard" when we switch on a Class enum value:
const class_name = switch (c.class) {
.wizard => "Wizard",
.thief => "Thief",
.bard => "Bard",
.warrior => "Warrior",
};
std.debug.print("{s} (G:{} H:{} XP:{})\n", .{
class_name,
c.gold,
c.health,
c.experience,
});
}
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