Lodash 源码分析

# unicodeWords

# Description

将一个 Unicode 字符串分割成一个单词数组。

# Params

{String} string

# Return

Array

# Code

/** Used to compose unicode character classes. */
const rsAstralRange = '\\ud800-\\udfff'
const rsComboMarksRange = '\\u0300-\\u036f'
const reComboHalfMarksRange = '\\ufe20-\\ufe2f'
const rsComboSymbolsRange = '\\u20d0-\\u20ff'
const rsComboMarksExtendedRange = '\\u1ab0-\\u1aff'
const rsComboMarksSupplementRange = '\\u1dc0-\\u1dff'
const rsComboRange = rsComboMarksRange + reComboHalfMarksRange + rsComboSymbolsRange + rsComboMarksExtendedRange + rsComboMarksSupplementRange
const rsDingbatRange = '\\u2700-\\u27bf'
const rsLowerRange = 'a-z\\xdf-\\xf6\\xf8-\\xff'
const rsMathOpRange = '\\xac\\xb1\\xd7\\xf7'
const rsNonCharRange = '\\x00-\\x2f\\x3a-\\x40\\x5b-\\x60\\x7b-\\xbf'
const rsPunctuationRange = '\\u2000-\\u206f'
const rsSpaceRange = ' \\t\\x0b\\f\\xa0\\ufeff\\n\\r\\u2028\\u2029\\u1680\\u180e\\u2000\\u2001\\u2002\\u2003\\u2004\\u2005\\u2006\\u2007\\u2008\\u2009\\u200a\\u202f\\u205f\\u3000'
const rsUpperRange = 'A-Z\\xc0-\\xd6\\xd8-\\xde'
const rsVarRange = '\\ufe0e\\ufe0f'
const rsBreakRange = rsMathOpRange + rsNonCharRange + rsPunctuationRange + rsSpaceRange

/** Used to compose unicode capture groups. */
const rsApos = "['\u2019]"
const rsBreak = `[${rsBreakRange}]`
const rsCombo = `[${rsComboRange}]`
const rsDigit = '\\d'
const rsDingbat = `[${rsDingbatRange}]`
const rsLower = `[${rsLowerRange}]`
const rsMisc = `[^${rsAstralRange}${rsBreakRange + rsDigit + rsDingbatRange + rsLowerRange + rsUpperRange}]`
const rsFitz = '\\ud83c[\\udffb-\\udfff]'
const rsModifier = `(?:${rsCombo}|${rsFitz})`
const rsNonAstral = `[^${rsAstralRange}]`
const rsRegional = '(?:\\ud83c[\\udde6-\\uddff]){2}'
const rsSurrPair = '[\\ud800-\\udbff][\\udc00-\\udfff]'
const rsUpper = `[${rsUpperRange}]`
const rsZWJ = '\\u200d'

/** Used to compose unicode regexes. */
const rsMiscLower = `(?:${rsLower}|${rsMisc})`
const rsMiscUpper = `(?:${rsUpper}|${rsMisc})`
const rsOptContrLower = `(?:${rsApos}(?:d|ll|m|re|s|t|ve))?`
const rsOptContrUpper = `(?:${rsApos}(?:D|LL|M|RE|S|T|VE))?`
const reOptMod = `${rsModifier}?`
const rsOptVar = `[${rsVarRange}]?`
const rsOptJoin = `(?:${rsZWJ}(?:${[rsNonAstral, rsRegional, rsSurrPair].join('|')})${rsOptVar + reOptMod})*`
const rsOrdLower = '\\d*(?:1st|2nd|3rd|(?![123])\\dth)(?=\\b|[A-Z_])'
const rsOrdUpper = '\\d*(?:1ST|2ND|3RD|(?![123])\\dTH)(?=\\b|[a-z_])'
const rsSeq = rsOptVar + reOptMod + rsOptJoin
const rsEmoji = `(?:${[rsDingbat, rsRegional, rsSurrPair].join('|')})${rsSeq}`

const reUnicodeWords = RegExp([
  `${rsUpper}?${rsLower}+${rsOptContrLower}(?=${[rsBreak, rsUpper, '$'].join('|')})`,
  `${rsMiscUpper}+${rsOptContrUpper}(?=${[rsBreak, rsUpper + rsMiscLower, '$'].join('|')})`,
  `${rsUpper}?${rsMiscLower}+${rsOptContrLower}`,
  `${rsUpper}+${rsOptContrUpper}`,
  rsOrdUpper,
  rsOrdLower,
  `${rsDigit}+`,
  rsEmoji
].join('|'), 'g')

function unicodeWords(string) {
  return string.match(reUnicodeWords)
}

# Analyze

/[A-Z\xc0-\xd6\xd8-\xde]?[a-z\xdf-\xf6\xf8-\xff]+(?:['’](?:d|ll|m|re|s|t|ve))?(?=[\xac\xb1\xd7\xf7\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\xbf\u2000-\u206f \t\x0b\f\xa0\ufeff\n\r\u2028\u2029\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u3000]|[A-Z\xc0-\xd6\xd8-\xde]|$)|(?:[A-Z\xc0-\xd6\xd8-\xde]|[^\ud800-\udfff\xac\xb1\xd7\xf7\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\xbf\u2000-\u206f \t\x0b\f\xa0\ufeff\n\r\u2028\u2029\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u3000\d\u2700-\u27bfa-z\xdf-\xf6\xf8-\xffA-Z\xc0-\xd6\xd8-\xde])+(?:['’](?:D|LL|M|RE|S|T|VE))?(?=[\xac\xb1\xd7\xf7\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\xbf\u2000-\u206f \t\x0b\f\xa0\ufeff\n\r\u2028\u2029\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u3000]|[A-Z\xc0-\xd6\xd8-\xde](?:[a-z\xdf-\xf6\xf8-\xff]|[^\ud800-\udfff\xac\xb1\xd7\xf7\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\xbf\u2000-\u206f \t\x0b\f\xa0\ufeff\n\r\u2028\u2029\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u3000\d\u2700-\u27bfa-z\xdf-\xf6\xf8-\xffA-Z\xc0-\xd6\xd8-\xde])|$)|[A-Z\xc0-\xd6\xd8-\xde]?(?:[a-z\xdf-\xf6\xf8-\xff]|[^\ud800-\udfff\xac\xb1\xd7\xf7\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\xbf\u2000-\u206f \t\x0b\f\xa0\ufeff\n\r\u2028\u2029\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u3000\d\u2700-\u27bfa-z\xdf-\xf6\xf8-\xffA-Z\xc0-\xd6\xd8-\xde])+(?:['’](?:d|ll|m|re|s|t|ve))?|[A-Z\xc0-\xd6\xd8-\xde]+(?:['’](?:D|LL|M|RE|S|T|VE))?|\d*(?:1ST|2ND|3RD|(?![123])\dTH)(?=\b|[a-z_])|\d*(?:1st|2nd|3rd|(?![123])\dth)(?=\b|[A-Z_])|\d+|(?:[\u2700-\u27bf]|(?:\ud83c[\udde6-\uddff]){2}|[\ud800-\udbff][\udc00-\udfff])[\ufe0e\ufe0f]?(?:[\u0300-\u036f\ufe20-\ufe2f\u20d0-\u20ff\u1ab0-\u1aff\u1dc0-\u1dff]|\ud83c[\udffb-\udfff])?(?:\u200d(?:[^\ud800-\udfff]|(?:\ud83c[\udde6-\uddff]){2}|[\ud800-\udbff][\udc00-\udfff])[\ufe0e\ufe0f]?(?:[\u0300-\u036f\ufe20-\ufe2f\u20d0-\u20ff\u1ab0-\u1aff\u1dc0-\u1dff]|\ud83c[\udffb-\udfff])?)*/

本质就是根据这个正则进行字符串的 match 分割

# Remark

  1. match MDN (opens new window)
  2. 关于 Unicode 相关可以参考 hasUnicode 源码分析

# Example

unicodeWords('微信 wechat 微笑🙂') // [ '微信', 'wechat', '微笑', '🙂' ]
unicodeWords('i test the performance of both in chrome\\firefox\\safari, slice always faster than loop.') 
/*
    [
      'i',       'test',
      'the',     'performance',
      'of',      'both',
      'in',      'chrome',
      'firefox', 'safari',
      'slice',   'always',
      'faster',  'than',
      'loop'
    ]
*/

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