SortedLinkedList

A tiny PHP library that provides a sorted singly-linked list which accepts either ints or strings (but not both). The list keeps values in sorted order as values are added.

Installation

Install with Composer:

composer require davidvarney/sortedlinkedlist

For development (to run tests):

composer install

Basic usage

use DavidVarney\SortedLinkedList\SortedLinkedList;

$list = new SortedLinkedList();
$list->add(5);
$list->add(1);
$list->add(3);

// returns [1, 3, 5]
print_r($list->toArray());

// string join with default glue ", "
echo $list->toString(); // "1, 3, 5"

// type information
echo $list->getType(); // "int"

$list->clear();

$list->add('banana');
$list->add('apple');
echo $list->toString('|'); // "apple|banana"

Notes:

• The list enforces type consistency: once you add an int the list only accepts ints; same for strings.
• Attempting to add the other type throws an InvalidArgumentException.

API

• add(int|string $value): void — Insert a value in sorted order.
• remove(int|string $value): bool — Remove a value; returns true if removed.
• toArray(): array — Return the list as an array of values.
• toString(string $glue = ', '): string — Return a joined string of values.
• contains(int|string $value): bool — Check presence of a value.
• isEmpty(): bool — Check if the list is empty.
• clear(): void — Clear the list and reset the stored type.
• getType(): ?string — Returns 'int', 'string', or null for empty list.

Running tests

This project uses PHPUnit (configured in phpunit.xml). Run the tests with the vendored PHPUnit binary:

./vendor/bin/phpunit

For a more readable output use testdox:

./vendor/bin/phpunit --testdox

Test coverage

This repository doesn't include a coverage tool by default, but you can generate coverage with Xdebug or PCOV installed and PHPUnit's --coverage-html option. Example (requires Xdebug enabled):

./vendor/bin/phpunit --coverage-html coverage

# open coverage/index.html in your browser

CI / PHPStan

This repository runs PHPStan via GitHub Actions on push and pull_request to main.

To run PHPStan locally after installing dev dependencies:

./vendor/bin/phpstan analyse -c phpstan.neon

License

MIT