What is diff-sequences?
The diff-sequences package is a utility for finding the longest common subsequence of items in two sequences (arrays). It is typically used for comparing sequences to determine the changes necessary to convert one sequence into another, which is useful in various applications such as diff tools, merging changes, and more.
What are diff-sequences's main functionalities?
Finding Longest Common Subsequence (LCS)
This feature allows you to find the longest common subsequence between two arrays. The provided code sample demonstrates how to use the package to compare two arrays and log the LCS.
const diff = require('diff-sequences');
const a = [1, 2, 3, 4, 5];
const b = [2, 3, 5];
const isCommon = (aIndex, bIndex) => a[aIndex] === b[bIndex];
let result = '';
const foundSubsequence = diff(a.length, b.length, isCommon, (nCommon, aCommon, bCommon) => {
for (let i = 0; i < nCommon; i++) {
result += a[aCommon + i];
}
});
console.log(result); // '235'
Other packages similar to diff-sequences
fast-diff
fast-diff is a JavaScript implementation of the O(ND) difference algorithm. It is used to quickly compute the difference between two strings and can return the result as an array of parts indicating if they are in the first string, second string, or both. It is similar to diff-sequences but is specifically optimized for string comparison rather than generic sequences.
jsdiff
jsdiff (also known as diff) is a library that provides several algorithms for string comparison, including character-by-character, word-by-word, and line-by-line diffs. It offers more features than diff-sequences, such as applying patches or computing diffs in different formats (e.g., JSON). It is more feature-rich but also larger and potentially slower for simple LCS computations.
google-diff-match-patch
google-diff-match-patch is a comprehensive library for performing operations required for synchronizing plain text. It includes algorithms for diff, match, and patch operations. It is more complex and feature-complete compared to diff-sequences, which is more focused on the specific task of finding the longest common subsequence.