prexp 0.1.2

Convert the path string to a regular expression, such as `/users/:name` and the like.

Prexp

Prexp (Path to regular expression) is a Dart package that converts a path to a regular expression.

import 'package:prexp/prexp.dart';

void main() {
  final String route = r'/users/:name';

  final Prexp prexp = Prexp.fromString(route);
  print(prexp.hasMatch('/users/odroe')); // true

  final PathMatcher matcher = PathMatcher.fromPrexp(prexp);
  print(matcher('/users/odroe')); // (PrexpMatch(/users/Seven, {name: Seven}))

  final PathBuilder builder = PathBuilder.fromPath(route);
  print(builder({'name': 'odroe'})); // /users/odroe

  print(Prexp.parse(
      route)); // [StringPrexpToken(/users), MetadataPrexpToken({"name":"name","prefix":"/","suffix":"","pattern":"[^\\/#\\?]+?","modifier":""}]
}

Installation

Add this to your package's pubspec.yaml file:

dependencies:
  prexp: latest

Or install it from the command line:

dart pub add prexp

Create a list of PrexpToken

The Prexp.parse static utility to create an list of PrexpToken from a path.

final Iterable<PrexpToken> tokens = Prexp.parse('/users/:name');

Optional parameters

• delimiter - The delimiter between segments. Defaults to /#?.
• prefixes - The prefixes to use when parsing a path. Defaults to ./.

Prexp class

Prexp implements the RegExp interface and is compatible with RegExp. The only difference between Prexp and RegExp is that Prexp contains the parameter source information of path.

final Prexp prexp = Prexp.fromString('/users/:name');

print(prexp.hasMatch('/users/odroe')); // true
print(prexp is RegExp); // true
print(prexp.metadata); // MetadataPrexpToken({"name":"name","prefix":"/","suffix":"","pattern":"[^\\/#\\?]+?","modifier":""})

Create a Prexp from a string

final Prexp prexp = Prexp.fromString('/users/:name');

Create a Prexp from a RegExp

final RegExp regexp = ...;
final Prexp prexp = Prexp.fromRegExp(regexp);

Create a Prexp from a list of PrexpToken

final Iterable<PrexpToken> tokens = Prexp.parse('/users/:name');
final Prexp prexp = Prexp.fromTokens(tokens);

Path builder

The PathBuilder class is used to build a path from a map of parameters.

Create a PathBuilder from a path

final PathBuilder builder = PathBuilder.fromPath('/users/:name');

print(builder({'name': 'odroe'})); // /users/odroe

Create a PathBuilder from list of PrexpToken

final Iterable<PrexpToken> tokens = Prexp.parse('/users/:name');
final PathBuilder builder = PathBuilder.fromTokens(tokens);

print(builder({'name': 'odroe'})); // /users/odroe

Path matcher

The PathMatcher class is used to match a path against a route.

Create a PathMatcher from a Prexp

final Prexp prexp = Prexp.fromString('/users/:name');
final PathMatcher matcher = PathMatcher.fromPrexp(prexp);

print(matcher('/users/odroe')); // (PrexpMatch(/users/odroe, {name: odroe}))

Create a PathMatcher from a RegExp

final RegExp regexp = ...;
final Iterable<MetadataPrexpToken> metadata = ...;
final PathMatcher matcher = PathMatcher.fromRegExp(regexp, metadata);

print(matcher('/users/odroe'));

Match a path against a route

final PathMatcher matcher = ...;
final Iterable<PrexpMatch> matches = matcher('/users/odroe');

print(matches); // (PrexpMatch(/users/odroe, {name: odroe}))

Note: If the path does not match the route, the PathMatcher returns an empty list.