From f71f1d66d6545fff6c10b1e30648901bf1c4b795 Mon Sep 17 00:00:00 2001 From: Brian Gianforcaro Date: Mon, 27 Sep 2021 18:28:46 -0700 Subject: [PATCH] Documentation: Add operator"" sv pattern to Patterns.md --- Documentation/Patterns.md | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/Documentation/Patterns.md b/Documentation/Patterns.md index 9870321e1150d3..425d7c6324f66b 100644 --- a/Documentation/Patterns.md +++ b/Documentation/Patterns.md @@ -80,3 +80,35 @@ struct Empty { }; static_assert(AssertSize()); ``` + +## String View Literals + +`AK::StringView` support for `operator"" sv` which is a special string literal operator that was added as of +[C++17 to enable `std::string_view` literals](https://en.cppreference.com/w/cpp/string/basic_string_view/operator%22%22sv). + +```cpp +[[nodiscard]] ALWAYS_INLINE constexpr AK::StringView operator"" sv(const char* cstring, size_t length) +{ + return AK::StringView(cstring, length); +} +``` + +This allows `AK::StringView` to be constructed from string literals with no runtime +cost to find the string length, and the data the `AK::StringView` points to will +reside in the data section of the binary. + +Example Usage: +```cpp +#include +#include +#include + +TEST_CASE(string_view_literal_operator) +{ + StringView literal_view = "foo"sv; + String test_string = "foo"; + + EXPECT_EQ(literal_view.length(), test_string.length()); + EXPECT_EQ(literal_view, test_string); +} +```