@carrotsearch/gatsby-transformer-html/src/replace-variables.js

A Gatsby transformer plugin for authoring content in HTML. Supports ToC generation, responsive images, section anchors and HighlightJS code highlighting.

const VARIABLE_WITH_DELIMITER_REGEX = /\$(\w+)\$/g;
exports.replaceVariables = (html, replacer) => {
  return html.replace(VARIABLE_WITH_DELIMITER_REGEX, (match, name, offset) =>
    replacer(name, offset)
  );
};

const VARIABLE_REGEX = /^\w+$/;
exports.validateVariables = variables => {
  // Validate variable names
  if (!variables) {
    return;
  }
  const offending = Object.keys(variables).filter(v => !VARIABLE_REGEX.test(v));
  if (offending.length > 0) {
    throw (
      "Variable names must match [A-Za-z0-9_], offending names: " +
      offending.join(", ") +
      "."
    );
  }
};

exports.createMapReplacer = map => {
  return name => map[name];
};