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vendor/github.com/mitchellh/hashstructure/README.md

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+# hashstructure [![GoDoc](https://godoc.org/github.com/mitchellh/hashstructure?status.svg)](https://godoc.org/github.com/mitchellh/hashstructure)
+
+hashstructure is a Go library for creating a unique hash value
+for arbitrary values in Go.
+
+This can be used to key values in a hash (for use in a map, set, etc.)
+that are complex. The most common use case is comparing two values without
+sending data across the network, caching values locally (de-dup), and so on.
+
+## Features
+
+  * Hash any arbitrary Go value, including complex types.
+
+  * Tag a struct field to ignore it and not affect the hash value.
+
+  * Tag a slice type struct field to treat it as a set where ordering
+    doesn't affect the hash code but the field itself is still taken into
+    account to create the hash value.
+
+  * Optionally specify a custom hash function to optimize for speed, collision
+    avoidance for your data set, etc.
+  
+  * Optionally hash the output of `.String()` on structs that implement fmt.Stringer,
+    allowing effective hashing of time.Time
+
+## Installation
+
+Standard `go get`:
+
+```
+$ go get github.com/mitchellh/hashstructure
+```
+
+## Usage & Example
+
+For usage and examples see the [Godoc](http://godoc.org/github.com/mitchellh/hashstructure).
+
+A quick code example is shown below:
+
+```go
+type ComplexStruct struct {
+    Name     string
+    Age      uint
+    Metadata map[string]interface{}
+}
+
+v := ComplexStruct{
+    Name: "mitchellh",
+    Age:  64,
+    Metadata: map[string]interface{}{
+        "car":      true,
+        "location": "California",
+        "siblings": []string{"Bob", "John"},
+    },
+}
+
+hash, err := hashstructure.Hash(v, nil)
+if err != nil {
+    panic(err)
+}
+
+fmt.Printf("%d", hash)
+// Output:
+// 2307517237273902113
+```