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vendor/github.com/modern-go/reflect2/README.md

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+# reflect2
+
+[![Sourcegraph](https://sourcegraph.com/github.com/modern-go/reflect2/-/badge.svg)](https://sourcegraph.com/github.com/modern-go/reflect2?badge)
+[![GoDoc](http://img.shields.io/badge/go-documentation-blue.svg?style=flat-square)](http://godoc.org/github.com/modern-go/reflect2)
+[![Build Status](https://travis-ci.org/modern-go/reflect2.svg?branch=master)](https://travis-ci.org/modern-go/reflect2)
+[![codecov](https://codecov.io/gh/modern-go/reflect2/branch/master/graph/badge.svg)](https://codecov.io/gh/modern-go/reflect2)
+[![rcard](https://goreportcard.com/badge/github.com/modern-go/reflect2)](https://goreportcard.com/report/github.com/modern-go/reflect2)
+[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://raw.githubusercontent.com/modern-go/reflect2/master/LICENSE)
+
+reflect api that avoids runtime reflect.Value cost
+
+* reflect get/set interface{}, with type checking
+* reflect get/set unsafe.Pointer, without type checking
+* `reflect2.TypeByName` works like `Class.forName` found in java
+
+[json-iterator](https://github.com/json-iterator/go) use this package to save runtime dispatching cost.
+This package is designed for low level libraries to optimize reflection performance.
+General application should still use reflect standard library.
+
+# reflect2.TypeByName
+
+```go
+// given package is github.com/your/awesome-package
+type MyStruct struct {
+	// ...
+}
+
+// will return the type
+reflect2.TypeByName("awesome-package.MyStruct")
+// however, if the type has not been used
+// it will be eliminated by compiler, so we can not get it in runtime
+```
+
+# reflect2 get/set interface{}
+
+```go
+valType := reflect2.TypeOf(1)
+i := 1
+j := 10
+valType.Set(&i, &j)
+// i will be 10
+```
+
+to get set `type`, always use its pointer `*type`
+
+# reflect2 get/set unsafe.Pointer
+
+```go
+valType := reflect2.TypeOf(1)
+i := 1
+j := 10
+valType.UnsafeSet(unsafe.Pointer(&i), unsafe.Pointer(&j))
+// i will be 10
+```
+
+to get set `type`, always use its pointer `*type`
+
+# benchmark
+
+Benchmark is not necessary for this package. It does nothing actually.
+As it is just a thin wrapper to make go runtime public. 
+Both `reflect2` and `reflect` call same function 
+provided by `runtime` package exposed by go language.
+
+# unsafe safety
+
+Instead of casting `[]byte` to `sliceHeader` in your application using unsafe.
+We can use reflect2 instead. This way, if `sliceHeader` changes in the future,
+only reflect2 need to be upgraded.
+
+reflect2 tries its best to keep the implementation same as reflect (by testing).