Adds demo.

demo.zig

@@ -0,0 +1,35 @@
+const std = @import("std");
+const argsParser = @import("args");
+
+pub fn main() !void {
+    var args = std.process.args();
+
+    var argsAllocator = std.heap.direct_allocator;
+
+    const exeName = try (args.next(argsAllocator) orelse {
+        try std.io.getStdErr().outStream().stream.write("Failed to get executable name from the argument list!\n");
+        return;
+    });
+    defer argsAllocator.free(exeName);
+
+    const options = try argsParser.parse(struct {
+        output: ?[]const u8 = null,
+        @"with-offset": bool = false,
+        @"with-hexdump": bool = false,
+        @"intermix-source": bool = false,
+        numberOfBytes: ?i32 = null,
+
+        pub const shorthands = .{
+            .S = "intermix-source",
+            .b = "with-hexdump",
+            .O = "with-offset",
+            .o = "output",
+        };
+    }, &args, argsAllocator);
+    defer options.deinit();
+
+    std.debug.warn("parsed result:\n{}\npositionals:\n", .{options.options});
+    for (options.args) |arg| {
+        std.debug.warn("\t{}\n", .{arg});
+    }
+}