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luhn-generator

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A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm

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var baseRepeat = require('./_baseRepeat'), baseToString = require('./_baseToString'), castSlice = require('./_castSlice'), hasUnicode = require('./_hasUnicode'), stringSize = require('./_stringSize'), stringToArray = require('./_stringToArray'); /* Built-in method references for those with the same name as other `lodash` methods. */ var nativeCeil = Math.ceil; /** * Creates the padding for `string` based on `length`. The `chars` string * is truncated if the number of characters exceeds `length`. * * @private * @param {number} length The padding length. * @param {string} [chars=' '] The string used as padding. * @returns {string} Returns the padding for `string`. */ function createPadding(length, chars) { chars = chars === undefined ? ' ' : baseToString(chars); var charsLength = chars.length; if (charsLength < 2) { return charsLength ? baseRepeat(chars, length) : chars; } var result = baseRepeat(chars, nativeCeil(length / stringSize(chars))); return hasUnicode(chars) ? castSlice(stringToArray(result), 0, length).join('') : result.slice(0, length); } module.exports = createPadding;