zig

test_pointer_casting.zig (812B) - Raw

---

 const std = @import("std");
 const expect = std.testing.expect;
 
 test "pointer casting" {
     const bytes align(@alignOf(u32)) = [_]u8{ 0x12, 0x12, 0x12, 0x12 };
     const u32_ptr: *const u32 = @ptrCast(&bytes);
     try expect(u32_ptr.* == 0x12121212);
 
     // Even this example is contrived - there are better ways to do the above than
     // pointer casting. For example, using a slice narrowing cast:
     const u32_value = std.mem.bytesAsSlice(u32, bytes[0..])[0];
     try expect(u32_value == 0x12121212);
 
     // And even another way, the most straightforward way to do it:
     try expect(@as(u32, @bitCast(bytes)) == 0x12121212);
 }
 
 test "pointer child type" {
     // pointer types have a `child` field which tells you the type they point to.
     try expect(@typeInfo(*u32).pointer.child == u32);
 }
 
 // test