xmlchars

What is xmlchars?

The xmlchars npm package is designed to provide utilities for working with XML characters. It offers functions to validate and handle XML character sets according to the XML specification. This package is useful for developers working with XML data, ensuring that the content they work with is compliant with XML standards.

What are xmlchars's main functionalities?

XML 1.0 Name Character Validation

This feature allows you to check if a character or a string of characters is valid according to XML 1.0 specifications for names. This is useful for validating XML tag names and attribute names.

const xmlchars = require('xmlchars');

const isValid = xmlchars.XML_1_0.isNameChar('a');
console.log(isValid); // Outputs: true

XML 1.1 Name Start Character Validation

This feature checks if a character can validly start an XML name in XML 1.1. It's essential for ensuring that names in XML documents adhere to the XML 1.1 specification.

const xmlchars = require('xmlchars');

const isValid = xmlchars.XML_1_1.isNameStartChar('a');
console.log(isValid); // Outputs: true

Other packages similar to xmlchars

xml-name-validator

This package provides similar functionalities for validating XML names. It checks if strings are valid XML names or qualified names. Compared to xmlchars, xml-name-validator focuses more narrowly on name validation without addressing other character-related checks.

README

Utilities for determining whether characters belong to character classes defined by the XML specs.

Organization

It used to be that the library was contained in a single file and you could just import/require/what-have-you the xmlchars module. However, that setup did not work well for people who cared about code optimization. Importing xmlchars meant importing all of the library and because of the way the code was generated there was no way to shake the resulting code tree.

Different modules cover different standards. At the time this documentation was last updated, we had:

• xmlchars/xml/1.0/ed5 which covers XML 1.0 edition 5.
• xmlchars/xml/1.0/ed4 which covers XML 1.0 edition 4.
• xmlchars/xml/1.1/ed2 which covers XML 1.0 edition 2.
• xmlchars/xmlns/1.0/ed3 which covers XML Namespaces 1.0 edition 3.

Features

The "things" each module contains can be categorized as follows:

1. "Fragments": these are parts and pieces of regular expressions that correspond to the productions defined in the standard that the module covers. You'd use these to build regular expressions.

2. Regular expressions that correspond to the productions defined in the standard that the module covers.

3. Lists: these are arrays of characters that correspond to the productions.

4. Functions that test code points to verify whether they fit a production.