Let's start making help real.

src/args/args.zig

@@ -39,6 +39,8 @@ pub fn Marker(comptime T: type) type {
     };
 }
 
+pub const help = @import("./help.zig");
+
 /// <https://git.cutie.zone/lyssieth/zither/issues/1>
 pub fn parseArgs(comptime T: type, allocator: Allocator) !T {
     const args = try std.process.argsAlloc(allocator);

src/args/help.zig

@@ -0,0 +1,8 @@
+const std = @import("std");
+
+pub fn printHelp(comptime T: type, writer: std.io.AnyWriter) !void {
+    _ = T;
+    _ = writer;
+
+    return error.NotImplemented;
+}