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+# GJSON Path Syntax
+
+A GJSON Path is a text string syntax that describes a search pattern for quickly retreiving values from a JSON payload.
+
+This document is designed to explain the structure of a GJSON Path through examples.
+
+- [Path structure](#path-structure)
+- [Basic](#basic)
+- [Wildcards](#wildcards)
+- [Escape Character](#escape-character)
+- [Arrays](#arrays)
+- [Queries](#queries)
+- [Dot vs Pipe](#dot-vs-pipe)
+- [Modifiers](#modifiers)
+- [Multipaths](#multipaths)
+- [Literals](#literals)
+
+The definitive implemenation is [github.com/tidwall/gjson](https://github.com/tidwall/gjson).
+Use the [GJSON Playground](https://gjson.dev) to experiment with the syntax online.
+
+## Path structure
+
+A GJSON Path is intended to be easily expressed as a series of components seperated by a `.` character.
+
+Along with `.` character, there are a few more that have special meaning, including `|`, `#`, `@`, `\`, `*`, `!`, and `?`.
+
+## Example
+
+Given this JSON
+
+```json
+{
+ "name": {"first": "Tom", "last": "Anderson"},
+ "age":37,
+ "children": ["Sara","Alex","Jack"],
+ "fav.movie": "Deer Hunter",
+ "friends": [
+ {"first": "Dale", "last": "Murphy", "age": 44, "nets": ["ig", "fb", "tw"]},
+ {"first": "Roger", "last": "Craig", "age": 68, "nets": ["fb", "tw"]},
+ {"first": "Jane", "last": "Murphy", "age": 47, "nets": ["ig", "tw"]}
+ ]
+}
+```
+
+The following GJSON Paths evaluate to the accompanying values.
+
+### Basic
+
+In many cases you'll just want to retreive values by object name or array index.
+
+```go
+name.last "Anderson"
+name.first "Tom"
+age 37
+children ["Sara","Alex","Jack"]
+children.0 "Sara"
+children.1 "Alex"
+friends.1 {"first": "Roger", "last": "Craig", "age": 68}
+friends.1.first "Roger"
+```
+
+### Wildcards
+
+A key may contain the special wildcard characters `*` and `?`.
+The `*` will match on any zero+ characters, and `?` matches on any one character.
+
+```go
+child*.2 "Jack"
+c?ildren.0 "Sara"
+```
+
+### Escape character
+
+Special purpose characters, such as `.`, `*`, and `?` can be escaped with `\`.
+
+```go
+fav\.movie "Deer Hunter"
+```
+
+You'll also need to make sure that the `\` character is correctly escaped when hardcoding a path in your source code.
+
+```go
+// Go
+val := gjson.Get(json, "fav\\.movie") // must escape the slash
+val := gjson.Get(json, `fav\.movie`) // no need to escape the slash
+```
+
+```rust
+// Rust
+let val = gjson::get(json, "fav\\.movie") // must escape the slash
+let val = gjson::get(json, r#"fav\.movie"#) // no need to escape the slash
+```
+
+
+### Arrays
+
+The `#` character allows for digging into JSON Arrays.
+
+To get the length of an array you'll just use the `#` all by itself.
+
+```go
+friends.# 3
+friends.#.age [44,68,47]
+```
+
+### Queries
+
+You can also query an array for the first match by using `#(...)`, or find all matches with `#(...)#`.
+Queries support the `==`, `!=`, `<`, `<=`, `>`, `>=` comparison operators,
+and the simple pattern matching `%` (like) and `!%` (not like) operators.
+
+```go
+friends.#(last=="Murphy").first "Dale"
+friends.#(last=="Murphy")#.first ["Dale","Jane"]
+friends.#(age>45)#.last ["Craig","Murphy"]
+friends.#(first%"D*").last "Murphy"
+friends.#(first!%"D*").last "Craig"
+```
+
+To query for a non-object value in an array, you can forgo the string to the right of the operator.
+
+```go
+children.#(!%"*a*") "Alex"
+children.#(%"*a*")# ["Sara","Jack"]
+```
+
+Nested queries are allowed.
+
+```go
+friends.#(nets.#(=="fb"))#.first >> ["Dale","Roger"]
+```
+
+*Please note that prior to v1.3.0, queries used the `#[...]` brackets. This was
+changed in v1.3.0 as to avoid confusion with the new [multipath](#multipaths)
+syntax. For backwards compatibility, `#[...]` will continue to work until the
+next major release.*
+
+The `~` (tilde) operator will convert a value to a boolean before comparison.
+
+For example, using the following JSON:
+
+```json
+{
+ "vals": [
+ { "a": 1, "b": true },
+ { "a": 2, "b": true },
+ { "a": 3, "b": false },
+ { "a": 4, "b": "0" },
+ { "a": 5, "b": 0 },
+ { "a": 6, "b": "1" },
+ { "a": 7, "b": 1 },
+ { "a": 8, "b": "true" },
+ { "a": 9, "b": false },
+ { "a": 10, "b": null },
+ { "a": 11 }
+ ]
+}
+```
+
+You can now query for all true(ish) or false(ish) values:
+
+```
+vals.#(b==~true)#.a >> [1,2,6,7,8]
+vals.#(b==~false)#.a >> [3,4,5,9,10,11]
+```
+
+The last value which was non-existent is treated as `false`
+
+### Dot vs Pipe
+
+The `.` is standard separator, but it's also possible to use a `|`.
+In most cases they both end up returning the same results.
+The cases where`|` differs from `.` is when it's used after the `#` for [Arrays](#arrays) and [Queries](#queries).
+
+Here are some examples
+
+```go
+friends.0.first "Dale"
+friends|0.first "Dale"
+friends.0|first "Dale"
+friends|0|first "Dale"
+friends|# 3
+friends.# 3
+friends.#(last="Murphy")# [{"first": "Dale", "last": "Murphy", "age": 44},{"first": "Jane", "last": "Murphy", "age": 47}]
+friends.#(last="Murphy")#.first ["Dale","Jane"]
+friends.#(last="Murphy")#|first <non-existent>
+friends.#(last="Murphy")#.0 []
+friends.#(last="Murphy")#|0 {"first": "Dale", "last": "Murphy", "age": 44}
+friends.#(last="Murphy")#.# []
+friends.#(last="Murphy")#|# 2
+```
+
+Let's break down a few of these.
+
+The path `friends.#(last="Murphy")#` all by itself results in
+
+```json
+[{"first": "Dale", "last": "Murphy", "age": 44},{"first": "Jane", "last": "Murphy", "age": 47}]
+```
+
+The `.first` suffix will process the `first` path on each array element *before* returning the results. Which becomes
+
+```json
+["Dale","Jane"]
+```
+
+But the `|first` suffix actually processes the `first` path *after* the previous result.
+Since the previous result is an array, not an object, it's not possible to process
+because `first` does not exist.
+
+Yet, `|0` suffix returns
+
+```json
+{"first": "Dale", "last": "Murphy", "age": 44}
+```
+
+Because `0` is the first index of the previous result.
+
+### Modifiers
+
+A modifier is a path component that performs custom processing on the JSON.
+
+For example, using the built-in `@reverse` modifier on the above JSON payload will reverse the `children` array:
+
+```go
+children.@reverse ["Jack","Alex","Sara"]
+children.@reverse.0 "Jack"
+```
+
+There are currently the following built-in modifiers:
+
+- `@reverse`: Reverse an array or the members of an object.
+- `@ugly`: Remove all whitespace from JSON.
+- `@pretty`: Make the JSON more human readable.
+- `@this`: Returns the current element. It can be used to retrieve the root element.
+- `@valid`: Ensure the json document is valid.
+- `@flatten`: Flattens an array.
+- `@join`: Joins multiple objects into a single object.
+- `@keys`: Returns an array of keys for an object.
+- `@values`: Returns an array of values for an object.
+- `@tostr`: Converts json to a string. Wraps a json string.
+- `@fromstr`: Converts a string from json. Unwraps a json string.
+- `@group`: Groups arrays of objects. See [e4fc67c](https://github.com/tidwall/gjson/commit/e4fc67c92aeebf2089fabc7872f010e340d105db).
+
+#### Modifier arguments
+
+A modifier may accept an optional argument. The argument can be a valid JSON payload or just characters.
+
+For example, the `@pretty` modifier takes a json object as its argument.
+
+```
+@pretty:{"sortKeys":true}
+```
+
+Which makes the json pretty and orders all of its keys.
+
+```json
+{
+ "age":37,
+ "children": ["Sara","Alex","Jack"],
+ "fav.movie": "Deer Hunter",
+ "friends": [
+ {"age": 44, "first": "Dale", "last": "Murphy"},
+ {"age": 68, "first": "Roger", "last": "Craig"},
+ {"age": 47, "first": "Jane", "last": "Murphy"}
+ ],
+ "name": {"first": "Tom", "last": "Anderson"}
+}
+```
+
+*The full list of `@pretty` options are `sortKeys`, `indent`, `prefix`, and `width`.
+Please see [Pretty Options](https://github.com/tidwall/pretty#customized-output) for more information.*
+
+#### Custom modifiers
+
+You can also add custom modifiers.
+
+For example, here we create a modifier which makes the entire JSON payload upper or lower case.
+
+```go
+gjson.AddModifier("case", func(json, arg string) string {
+ if arg == "upper" {
+ return strings.ToUpper(json)
+ }
+ if arg == "lower" {
+ return strings.ToLower(json)
+ }
+ return json
+})
+"children.@case:upper" ["SARA","ALEX","JACK"]
+"children.@case:lower.@reverse" ["jack","alex","sara"]
+```
+
+*Note: Custom modifiers are not yet available in the Rust version*
+
+### Multipaths
+
+Starting with v1.3.0, GJSON added the ability to join multiple paths together
+to form new documents. Wrapping comma-separated paths between `[...]` or
+`{...}` will result in a new array or object, respectively.
+
+For example, using the given multipath:
+
+```
+{name.first,age,"the_murphys":friends.#(last="Murphy")#.first}
+```
+
+Here we selected the first name, age, and the first name for friends with the
+last name "Murphy".
+
+You'll notice that an optional key can be provided, in this case
+"the_murphys", to force assign a key to a value. Otherwise, the name of the
+actual field will be used, in this case "first". If a name cannot be
+determined, then "_" is used.
+
+This results in
+
+```json
+{"first":"Tom","age":37,"the_murphys":["Dale","Jane"]}
+```
+
+### Literals
+
+Starting with v1.12.0, GJSON added support of json literals, which provides a way for constructing static blocks of json. This is can be particularly useful when constructing a new json document using [multipaths](#multipaths).
+
+A json literal begins with the '!' declaration character.
+
+For example, using the given multipath:
+
+```
+{name.first,age,"company":!"Happysoft","employed":!true}
+```
+
+Here we selected the first name and age. Then add two new fields, "company" and "employed".
+
+This results in
+
+```json
+{"first":"Tom","age":37,"company":"Happysoft","employed":true}
+```
+
+*See issue [#249](https://github.com/tidwall/gjson/issues/249) for additional context on JSON Literals.*