65 lines
2.0 KiB
Zig
65 lines
2.0 KiB
Zig
//
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// Enums are really just a set of numbers. You can leave the
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// numbering up to the compiler, or you can assign them
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// explicitly. You can even specify the numeric type used.
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//
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// const Stuff = enum(u8){ foo = 16 };
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//
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// You can get the integer out with a builtin function,
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// @enumToInt(). We'll learn about builtins properly in a later
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// exercise.
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//
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// var my_stuff: u8 = @enumToInt(Stuff.foo);
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//
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// Note how that built-in function starts with "@" just like the
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// @import() function we've been using.
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//
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const std = @import("std");
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// Zig lets us write integers in hexadecimal format:
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//
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// 0xf (is the value 15 in hex)
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//
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// Web browsers let us specify colors using a hexadecimal
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// number where each byte represents the brightness of the
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// Red, Green, or Blue component (RGB) where two hex digits
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// are one byte with a value range of 0-255:
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//
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// #RRGGBB
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//
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// Please define and use a pure blue value Color:
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const Color = enum(u32) {
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red = 0xff0000,
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green = 0x00ff00,
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blue = 0x0000ff,
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};
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pub fn main() void {
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// Remember Zig's multi-line strings? Here they are again.
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// Also, check out this cool format string:
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//
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// {x:0>6}
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// ^
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// x type ('x' is lower-case hexadecimal)
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// : separator (needed for format syntax)
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// 0 padding character (default is ' ')
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// > alignment ('>' aligns right)
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// 6 width (use padding to force width)
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//
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// Please add this formatting to the blue value.
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// (Even better, experiment without it, or try parts of it
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// to see what prints!)
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std.debug.print(
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\\<p>
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\\ <span style="color: #{x:0>6}">Red</span>
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\\ <span style="color: #{x:0>6}">Green</span>
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\\ <span style="color: #{x:0>6}">Blue</span>
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\\</p>
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\\
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, .{
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@enumToInt(Color.red),
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@enumToInt(Color.green),
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@enumToInt(Color.blue), // Oops! We're missing something!
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});
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}
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