code-excerpt

What is code-excerpt?

The code-excerpt npm package is designed to extract and highlight excerpts from code snippets. It is particularly useful for creating documentation, tutorials, or any content that requires displaying code with specific lines highlighted.

What are code-excerpt's main functionalities?

Extracting Code Excerpts

This feature allows you to extract a specific range of lines from a code snippet. The `start` and `end` options specify the range of lines to be extracted.

const codeExcerpt = require('code-excerpt');
const code = `
function add(a, b) {
  return a + b;
}

console.log(add(2, 3));
`;
const excerpt = codeExcerpt(code, { start: 2, end: 4 });
console.log(excerpt);
// Output:
// {
//   value: '  return a + b;\n}\n\nconsole.log(add(2, 3));\n',
//   start: 2,
//   end: 4
// }

Highlighting Specific Lines

This feature allows you to highlight specific lines within the extracted code excerpt. The `highlight` option takes an array of line numbers to be highlighted.

const codeExcerpt = require('code-excerpt');
const code = `
function add(a, b) {
  return a + b;
}

console.log(add(2, 3));
`;
const excerpt = codeExcerpt(code, { start: 2, end: 4, highlight: [3] });
console.log(excerpt);
// Output:
// {
//   value: '  return a + b;\n}\n\nconsole.log(add(2, 3));\n',
//   start: 2,
//   end: 4,
//   highlight: [3]
// }

Other packages similar to code-excerpt

highlight.js

highlight.js is a popular library for syntax highlighting of code snippets. Unlike code-excerpt, which focuses on extracting and highlighting specific lines, highlight.js is designed to apply syntax highlighting to entire code blocks. It supports a wide range of programming languages and is highly customizable.

prismjs

Prism is a lightweight, extensible syntax highlighter. It is similar to highlight.js in that it focuses on syntax highlighting for entire code blocks. Prism is known for its performance and ease of use, and it also supports a wide range of languages and plugins for additional functionality.

codemirror

CodeMirror is a versatile text editor implemented in JavaScript for the browser. It is more than just a syntax highlighter; it provides a full-featured code editor with features like autocompletion, linting, and more. While it can be used to highlight code, its primary use case is as an in-browser code editor.

README

code-excerpt

Extract code excerpts

Install

$ npm install --save code-excerpt

Usage

const codeExcerpt = require('code-excerpt');

const source = `
'use strict';

function someFunc() {}

module.exports = () => {
	const a = 1;
	const b = 2;
	const c = 3;

	someFunc();
};
`.trim();

const excerpt = codeExcerpt(source, 5);
//=> [
//	{line: 2, value: '                        '},
//	{line: 3, value: 'function someFunc() {}  '},
//	{line: 4, value: '                        '},
//	{line: 5, value: 'module.exports = () => {'},
//	{line: 6, value: '  const a = 1;          '},
//	{line: 7, value: '  const b = 2;          '},
//	{line: 8, value: '  const c = 3;          '}
// ]

API

codeExcerpt(source, line, [options])

All lines in the output have equal width for convenience (customizable via options.equalLength). For example, if a line needs to be highlighted, the highlight will be full-width, just like in editors.

source

Type: string

Source code.

line

Type: number

Line number to extract excerpt for.

options

around

Type: number
Default: 3

Number of surrounding lines to extract.

equalLength

Type: boolean
Default: true

Extend lines to the same length. Useful for highlighting lines.

License

MIT © vdemedes