A collection of utility functions for string manipulation.

StringUtil.ts

/**
 * StringUtil.ts
 *
 * A collection of utility functions for string manipulation.
 * 
 * Attribution: Custom implementations inspired by common JavaScript practices.
 * 
 * ## Contents:
 * - `trimWhitespace(str)`: Removes leading and trailing whitespace from a string.
 * - `toCamelCase(str)`: Converts a string to camelCase.
 * - `splitIntoWords(str)`: Splits a string into an array of words.
 * - `capitalizeFirstLetter(str)`: Capitalizes the first letter of a string.
 * - `ensureLength(str, minLength)`: Ensures a string has at least a minimum length by padding with spaces.
 * - `leftPad(str, targetLength, padChar)`: Pads the start of a string with a specified character until it reaches a certain length.
 * - `removeSpaces(str)`: Removes all spaces from a string.
 * - `startsWithVowel(str)`: Checks if a string starts with a vowel.
 * - `endsWithConsonant(str)`: Checks if a string ends with a consonant.
 */

/**
 * Removes leading and trailing whitespace from a string.
 *
 * @param {string} str - The input string.
 * @returns {string} The trimmed string.
 */
export function trimWhitespace(str: string): string {
  return str.trim();
}

/**
 * Converts a string to camelCase.
 *
 * @param {string} str - The input string.
 * @returns {string} The camelCased string.
 */
export function toCamelCase(str: string): string {
  return str.replace(/(?:^\w|[A-Z]|\b\w)/g, function (word, index) {
    return index === 0 ? word.toLowerCase() : word.toUpperCase();
  }).replace(/\s+/g, '');
}

/**
 * Splits a string into an array of words.
 *
 * @param {string} str - The input string.
 * @returns {string[]} An array of words.
 */
export function splitIntoWords(str: string): string[] {
  return str.split(/\s+/);
}

/**
 * Capitalizes the first letter of a string.
 *
 * @param {string} str - The input string.
 * @returns {string} The capitalized string.
 */
export function capitalizeFirstLetter(str: string): string {
  return str.charAt(0).toUpperCase() + str.slice(1);
}

/**
 * Ensures a string has at least a minimum length by padding with spaces.
 *
 * @param {string} str - The input string.
 * @param {number} minLength - The minimum length the string should have.
 * @returns {string} The padded string.
 */
export function ensureLength(str: string, minLength: number): string {
  return str.padEnd(minLength, ' ');
}

/**
 * Pads the start of a string with a specified character until it reaches a certain length.
 *
 * @param {string} str - The input string.
 * @param {number} targetLength - The target length of the string after padding.
 * @param {string} padChar - The character to pad the string with.
 * @returns {string} The padded string.
 */
export function leftPad(str: string, targetLength: number, padChar: string = ' '): string {
  return str.padStart(targetLength, padChar);
}

/**
 * Removes all spaces from a string.
 *
 * @param {string} str - The input string.
 * @returns {string} The string without spaces.
 */
export function removeSpaces(str: string): string {
  return str.replace(/\s+/g, '');
}

/**
 * Checks if a string starts with a vowel.
 *
 * @param {string} str - The input string.
 * @returns {boolean} True if the string starts with a vowel, false otherwise.
 */
export function startsWithVowel(str: string): boolean {
  return ['a', 'e', 'i', 'o', 'u'].some(vowel => str[0].toLowerCase() === vowel);
}

/**
 * Checks if a string ends with a consonant.
 *
 * @param {string} str - The input string.
 * @returns {boolean} True if the string ends with a consonant, false otherwise.
 */
export function endsWithConsonant(str: string): boolean {
  return !['a', 'e', 'i', 'o', 'u'].includes(str[str.length - 1].toLowerCase());
}