Javascript Utilities

stringFunctions.js

/**
 * Split a string on whitespace, keeping within a maximum line length
 */
export function splitOnWhitespace(source, maxLength=90) {
    // If shorter than the maxLength, just return the source in an array
    if (source.length <= maxLength) {
      return [source];
    }

    // Find all space characters
    const spaces = [...source.matchAll(/\s+/g)].map(res => res.index);
    // Find the largest index before the maxLength
    const splitPoint = spaces.filter(i => i < maxLength).pop();

    // Return an array comprising...
    return [
      // the first line (up to the splitPoint)
      source.substring(0, splitPoint),
      // and a spread of the result of recursing into this function with the rest
      ...splitOnSpace(source.substring(splitPoint).trim(), maxLength)
    ];
}