example style fixes

manuals/meta_examples/enum_example.cpp

@@ -0,0 +1,59 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021-2022, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#include "../meta_manuals.hpp"
+
+namespace
+{
+    enum class align {
+        left,
+        right,
+        center,
+    };
+}
+
+TEST_CASE("meta/meta_examples/enum/type") {
+    namespace meta = meta_hpp;
+
+    // 'align' enumeration type registration
+    meta::enum_<align>()
+        .evalue_("left", align::left)
+        .evalue_("right", align::right)
+        .evalue_("center", align::center);
+
+    // resolves a enumeration type by enumerator
+    const meta::enum_type align_type = meta::resolve_type(align::left);
+
+    // also, it can be resolved by static enumeration type
+    CHECK(align_type == meta::resolve_type<align>());
+
+    // allows to know the underlying type
+    CHECK(align_type.get_underlying_type() == meta::resolve_type<int>());
+
+    // prints all enumerators
+    fmt::print("* align:\n");
+    for ( auto&& [index, evalue] : align_type.get_evalues() ) {
+        fmt::print("  - {}:{}\n", index.get_name(), evalue.get_underlying_value());
+    }
+}
+
+TEST_CASE("meta/meta_examples/enum/usage") {
+    namespace meta = meta_hpp;
+
+    const align e = align::center;
+
+    // resolves a enumeration type by enumerator instance 'e'
+    const meta::enum_type align_type = meta::resolve_type(e);
+
+    // converts the enumerator to its name
+    CHECK(align_type.value_to_name(e) == "center");
+
+    // also, it works with dynamic value types
+    CHECK(align_type.value_to_name(meta::uvalue{e}) == "center");
+
+    // ... and back again
+    CHECK(align_type.name_to_value("center") == e);
+}