48 lines
1.2 KiB
Zig
48 lines
1.2 KiB
Zig
//
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// Zig has an "unreachable" statement. Use it when you want to tell the
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// compiler that a branch of code should never be executed and that the
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// mere act of reaching it is an error.
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//
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// if (true) {
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// ...
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// } else {
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// unreachable;
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// }
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//
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// Here we've made a little virtual machine that performs mathematical
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// operations on a single numeric value. It looks great but there's one
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// little problem: the switch statement doesn't cover every possible
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// value of a u8 number!
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//
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// WE know there are only three operations but Zig doesn't. Use the
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// unreachable statement to make the switch complete. Or ELSE. :-)
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//
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const std = @import("std");
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pub fn main() void {
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const operations = [_]u8{ 1, 1, 1, 3, 2, 2 };
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var current_value: u32 = 0;
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for (operations) |op| {
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switch (op) {
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1 => {
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current_value += 1;
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},
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2 => {
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current_value -= 1;
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},
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3 => {
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current_value *= current_value;
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},
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else => {
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unreachable;
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},
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}
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std.debug.print("{} ", .{current_value});
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}
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std.debug.print("\n", .{});
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}
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