variadic GlProgram instead of initializer_list

libcygnet/include/cygnet/GlProgram.h

@@ -19,7 +19,7 @@ public:
 	GlShader(const char *source, Type type);
 	~GlShader();
 
-	GLuint id() { return id_; }
+	GLuint id() const { return id_; }
 
 private:
 	GLuint id_;
@@ -28,9 +28,14 @@ private:
 
 class GlProgram: NonCopyable {
 public:
-	GlProgram(std::initializer_list<std::reference_wrapper<GlShader>> shaders);
+	template <typename... T, typename = std::enable_if_t<std::conjunction_v<std::is_same<T, GlShader>...>>>
+	GlProgram(const T &... shaders): GlProgram() { (addShader(shaders), ...); link(); }
+	GlProgram() { id_ = glCreateProgram(); }
 	~GlProgram();
 
+	void addShader(const GlShader &shader) { glAttachShader(id_, shader.id()); }
+	void link();
+
 	void use() { glUseProgram(id_); }
 	GLuint id() { return id_; }
 	GLuint getLocation(const char *name) { return glGetAttribLocation(id_, name); }

libcygnet/include/cygnet/util.h

@@ -42,5 +42,4 @@ public:
 	~Deferred() { Func(); }
 };
 
-
 }

libcygnet/samples/hello-triangle/hello-triangle.cc

@@ -23,7 +23,7 @@ int main() {
 
 	Cygnet::GlShader vertex(vertexSource, Cygnet::GlShader::Type::VERTEX);
 	Cygnet::GlShader fragment(fragmentSource, Cygnet::GlShader::Type::FRAGMENT);
-	Cygnet::GlProgram program({ vertex, fragment });
+	Cygnet::GlProgram program(vertex, fragment);
 	GLuint positionAttrib = program.getLocation("position");
 	program.use();
 

libcygnet/src/GlProgram.cc

@@ -41,13 +41,8 @@ GlShader::~GlShader() {
 	}
 }
 
-GlProgram::GlProgram(std::initializer_list<std::reference_wrapper<GlShader>> shaders) {
-	id_ = glCreateProgram();
-
-	for (GlShader &shader: shaders) {
-		glAttachShader(id_, shader.id());
-	}
-
+void GlProgram::link() {
+	std::cout << "link\n";
 	glLinkProgram(id_);
 
 	char log[4096];