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readme.md

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+# C# StringLiteralGenerator
+
+A C# [Source Generator](https://github.com/dotnet/roslyn/blob/master/docs/features/source-generators.md) for optimizing UTF-8 binaries.
+
+Original source (mamual written):
+
+```cs
+namespace Sample
+{
+    partial class Literals
+    {
+        [StringLiteral.Utf8Attribute("aαあ😊")]
+        public static partial System.ReadOnlySpan<byte> S();
+    }
+}
+```
+
+Generated source:
+
+```cs
+namespace Sample
+{
+    partial class Literals
+    {
+        public static partial System.ReadOnlySpan<byte> S() => new byte[] {97, 206, 177, 227, 129, 130, 240, 159, 152, 138, };
+    }
+}
+```
+
+- Generates UTF-8 binary data from string literals (UTF-16).
+- The UTF-8 data is optimized to avoid allocation. see: [C# ReadOnlySpan and static data](https://vcsjones.dev/2019/02/01/csharp-readonly-span-bytes-static/)