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https://github.com/f3ath/rfc-6901-dart

JSON Pointer (RFC 6901) implementation in Dart
https://github.com/f3ath/rfc-6901-dart

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JSON Pointer (RFC 6901) implementation in Dart

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# [RFC 6901] JSON Pointer
JSON Pointer ([RFC 6901]) implementation in Dart.

Features:
- Reads, writes, removes values
- Fully implements the standard, including the `-` character
- Can build the entire path, e.g. `/foo/bar/-/baz`
- No external dependencies
- 100% test coverage

## Constructing pointers
A JSON Pointer object can be parsed from a string expression.
The expression MUST be a valid non-empty JSON Pointer expression with "/" and "~" escaped.
```dart
final pointer = JsonPointer('/foo/0/bar'); // a valid non-empty pointer
final alsoPointer = JsonPointer('/foo/-'); // a valid non-empty pointer with a special "-" reference
final emptyPointer = JsonPointer(); // an empty pointer

JsonPointer('oops'); // throws a FormatException: expression doesn't start with "/"
JsonPointer('/foo/~'); // throws a FormatException: unescaped "~"
```

It can also be built from individual reference tokens. In such case, it will escape the tokens automatically.
```dart
final pointer = JsonPointer.build(['foo', '0', 'bar/']); // Makes "/foo/0/bar~1"
final longerPointer = JsonPointerSegment('-', pointer); // Makes "/foo/0/bar~1/-"
final evenLongerPointer = JsonPointerSegment('wow', longerPointer); // Makes "/foo/0/bar~1/-/wow"
```

## Reading and writing values
The `read()` method returns the referenced value. The `write()` method returns a copy of the document with
the referenced value replaced by the new value.
```dart
import 'dart:convert';

import 'package:rfc_6901/rfc_6901.dart';

void main() {
const json = '{"foo": [{"bar": 42}]}';
final document = jsonDecode(json);
print('Original document: $document');

[
'/foo', // reads the array
'/foo/0', // reads the first element of the array
'/foo/0/bar', // reads 42
].forEach((expression) {
final pointer = JsonPointer(expression);
print('Pointer "$pointer" reads ${pointer.read(document)}');
});

[
'/foo/0/bar', // {foo: [{bar: banana}]}
'/foo/-', // {foo: [{bar: 42}, banana]}
'/a/b/-/c/d', // {foo: [{bar: 42}], a: {b: [{c: {d: banana}}]}}
].forEach((expression) {
final pointer = JsonPointer(expression);
final d = pointer.write(document, 'banana');
print('Add a banana at "$pointer": $d');
});
}
```

[RFC 6901]: https://tools.ietf.org/html/rfc6901