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);
+    }
 }

examples/request_reply.zig

@@ -0,0 +1,41 @@
+const std = @import("std");
+const nats = @import("nats");
+
+fn onMessage(
+    userdata: *bool,
+    connection: *nats.Connection,
+    subscription: *nats.Subscription,
+    message: *nats.Message,
+) void {
+    _ = subscription;
+
+    std.debug.print("Subject \"{s}\" received message: \"{s}\"\n", .{
+        message.getSubject(),
+        message.getData() orelse "[null]",
+    });
+
+    if (message.getReply()) |reply| {
+        connection.publishString(reply, "salutations") catch @panic("HELP");
+    }
+
+    userdata.* = true;
+}
+
+pub fn main() !void {
+    const connection = try nats.Connection.connectTo(nats.default_server_url);
+    defer connection.destroy();
+
+    var done = false;
+    const subscription = try connection.subscribe(bool, "channel", onMessage, &done);
+    defer subscription.destroy();
+
+    while (!done) {
+        const reply = try connection.requestString("channel", "greetings", 1000);
+        defer reply.destroy();
+
+        std.debug.print("Reply \"{s}\" got message: {s}\n", .{
+            reply.getSubject(),
+            reply.getData() orelse "[null]",
+        });
+    }
+}

src/nats.zig

@@ -38,40 +38,6 @@ pub const StatsCounts = sta_.StatsCounts;
 const Status = err_.Status;
 pub const Error = err_.Error;
 
-fn onMessage(userdata: *bool, connection: *Connection, subscription: *Subscription, message: *Message) void {
-    _ = subscription;
-
-    std.debug.print("Subject \"{s}\" received message: \"{s}\"\n", .{
-        message.getSubject(),
-        message.getData() orelse "[null]",
-    });
-
-    if (message.getReply()) |reply| {
-        connection.publishString(reply, "salutations") catch @panic("HELP");
-    }
-
-    userdata.* = true;
-}
-
-pub fn main() !void {
-    const connection = try Connection.connectTo(default_server_url);
-    defer connection.destroy();
-
-    var done = false;
-    const subscription = try connection.subscribe(bool, "channel", onMessage, &done);
-    defer subscription.destroy();
-
-    while (!done) {
-        const reply = try connection.requestString("channel", "greetings", 1000);
-        defer reply.destroy();
-
-        std.debug.print("Reply \"{s}\" got message: {s}\n", .{
-            reply.getSubject(),
-            reply.getData() orelse "[null]",
-        });
-    }
-}
-
 pub fn getVersion() [:0]const u8 {
     const verString = nats_c.nats_GetVersion();
     return std.mem.sliceTo(verString, 0);