Dart lookaround iterator #

The LookaroundIterator class exposes a fixed number of elements in the past and future of the current iteration element.

// `it` is an iterator over a list of the numbers 1..10, currently
// pointing at `4`.
final it = LookaroundIterator(
    List.generate(10, (n) => n + 1).iterator,
    lookbehind: 2,
    lookahead: 3)
  ..moveNext()
  ..moveNext()
  ..moveNext()
  ..moveNext();

// Prints _2, 3, 4, 5, 6, 7_.
// Notice the negative start index and the inclusive range `<=`.
for (int i = -it.lookbehind; i <= it.lookahead; i++) {
  print(it[i]);
}

Changelog #

1.0.1+1 #

Add SDK constraint so the package can be used in Dart 2.0.0.
Run dartfmt --fix.

1.0.1 #

Cosmetic changes to appease pana: Add analysis_options.yaml and CHANGELOG.md.
Fix strong_mode and linter warnings.
Update repository name in pubspec.yaml.

1.0.0 #

Initial version.

Use this package as a library

1. Depend on it

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


dependencies:
  lookaround_iterator: ^1.0.1+1

2. Install it

You can install packages from the command line:

with pub:


$ pub get

with Flutter:


$ flutter pub get

Alternatively, your editor might support pub get or flutter pub get. Check the docs for your editor to learn more.

3. Import it

Now in your Dart code, you can use:


import 'package:lookaround_iterator/lookaround_iterator.dart';

Version	Uploaded	Documentation	Archive
1.0.1+1	Nov 8, 2018
1.0.1	Dec 6, 2017
1.0.0	Aug 13, 2017

Popularity: Describes how popular the package is relative to other packages. [more]	0
Health: Code health derived from static analysis. [more]	99
Maintenance: Reflects how tidy and up-to-date the package is. [more]	90
Overall: Weighted score of the above. [more]	48

Learn more about scoring.

We analyzed this package on Jun 25, 2019, and provided a score, details, and suggestions below. Analysis was completed with status completed using:

Dart: 2.3.2
pana: 0.12.18

Platforms

Detected platforms: Flutter, web, other

No platform restriction found in primary library package:lookaround_iterator/lookaround_iterator.dart.

Health suggestions

Fix lib/lookaround_iterator.dart. (-1 points)

Analysis of lib/lookaround_iterator.dart reported 2 hints:

line 117 col 7: DO use curly braces for all flow control structures.

line 119 col 7: DO use curly braces for all flow control structures.

Maintenance suggestions

Maintain an example. (-10 points)

Create a short demo in the example/ directory to show how to use this package.

Common filename patterns include main.dart, example.dart, and lookaround_iterator.dart. Packages with multiple examples should provide example/README.md.

For more information see the pub package layout conventions.

Dependencies

Package	Constraint	Resolved	Available
Direct dependencies
Dart SDK	>=2.0.0 <3.0.0
Dev dependencies
test	^1.0.0

Dart pub

lookaround_iterator 1.0.1+1