als-replace-between

als-replace-between

The als-replace-between library provides a utility for replacing text between matched start and end points defined by regular expressions. It is designed to work both in Node.js and browser environments.

Installation

npm install als-replace-between

Usage

Quick Replacement

For a quick text replacement within specified boundaries:

const {replaceBetween} = require('als-replace-between');

const content = "Hello <start>world<end>!";
const modifiedContent = replaceBetween(content, /<start>/, /<end>/, [t => t.toUpperCase()]);

console.log(modifiedContent); // Outputs: Hello <START>WORLD<END>!

const content = "Hello <start>world, <start>again<end><end>!";
const modifiers = [
   t => t.replace(/>(.*?)</,(m,t) => m.replace(t,t.toUpperCase()))
]   
const replacer = new ReplaceBetween(content, /<start>/, /<end>/, modifiers);

console.log(replacer.result); // Outputs: Hello <start>WORLD, <start>AGAIN<end><end>!

Parameters

• content: The string within which text replacements are to be made. Must be a string.
• startR and endR: Regular expressions defining the start and end of the replacement boundaries.
• modifiers: An array of functions that each take a string segment and return a modified string. These functions can perform any operation, including further calls to ReplaceBetween.
• context (optional): An object that provides additional data accessible to modifiers.

Error Handling

Errors are thrown in the following scenarios:

• If content is not a string.
• If either startR or endR are not instances of RegExp.
• If modifiers is not an array.
• If there are unmatched start and end tags in the content.

Advanced usage

The folowing example will collect properties and will replace all {} to ${}.

const content = /*html*/`<div some={var}>{arr.map(item => item)}</div>`;
const modifiers = [
   (text,context,parent) => {
      if(parent.match(new RegExp(`\w*=${text}`))) context.props.push(text.slice(1,-1))
      return '$'+text
   }
];
const context = {props:[]}
const replacer = new ReplaceBetween(content, /\{/, /\}/, modifiers,context);

console.log(replacer.result); // <div some=${var}>${arr.map(item => item)}</div>
console.log(context) // {"props": ["var"]}