add examples and integrate into build

I suppose the next step will be to translate the C examples into their
zig counterparts. This is also good dog food.

build.zig

@@ -12,10 +12,11 @@ pub fn build(b: *std.Build) void {
         .source_file = .{ .path = "src/nats.zig" },
     });
 
-    const nats_c = nats_build.nats_c_lib(
-        b,
-        .{ .name = "nats-c", .target = target, .optimize = optimize },
-    );
+    const nats_c = nats_build.nats_c_lib(b, .{
+        .name = "nats-c",
+        .target = target,
+        .optimize = optimize,
+    });
 
     const tests = b.addTest(.{
         .root_source_file = .{ .path = "tests/main.zig" },
@@ -26,8 +27,49 @@ pub fn build(b: *std.Build) void {
     tests.addModule("nats", nats);
     tests.linkLibrary(nats_c);
 
-    b.installArtifact(tests);
     const run_main_tests = b.addRunArtifact(tests);
     const test_step = b.step("test", "Run tests");
     test_step.dependOn(&run_main_tests.step);
+
+    add_examples(b, .{
+        .target = target,
+        .optimize = optimize,
+        .nats_module = nats,
+        .nats_c = nats_c,
+    });
+}
+
+const ExampleOptions = struct {
+    target: std.zig.CrossTarget,
+    optimize: std.builtin.OptimizeMode,
+    nats_module: *std.Build.Module,
+    nats_c: *std.Build.Step.Compile,
+};
+
+const Example = struct {
+    name: []const u8,
+    file: []const u8,
+};
+
+const examples = [_]Example{
+    .{ .name = "request_reply", .file = "examples/request_reply.zig" },
+};
+
+pub fn add_examples(b: *std.build, options: ExampleOptions) void {
+    const example_step = b.step("examples", "build examples");
+
+    inline for (examples) |example| {
+        const ex_exe = b.addExecutable(.{
+            .name = example.name,
+            .root_source_file = .{ .path = example.file },
+            .target = options.target,
+            .optimize = options.optimize,
+        });
+
+        ex_exe.addModule("nats", options.nats_module);
+        ex_exe.linkLibrary(options.nats_c);
+
+        const install = b.addInstallArtifact(ex_exe, .{});
+        example_step.dependOn(&install.step);
+    }
 }