Use const/let instead of var

examples/cli.js

@@ -1,4 +1,4 @@
-var QRCode = require('../lib')
+const QRCode = require('../lib')
 
 QRCode.toString('yo yo yo', function (error, data) {
   if (error) {

examples/clientsideserver.js

@@ -1,12 +1,12 @@
-var express = require('express')
-var app = express()// .createServer()
-var http = require('http')
-var fs = require('fs')
-var QRCode = require('../lib')
-var canvasutil = require('canvasutil')
-var { createCanvas, loadImage } = require('canvas')
+const express = require('express')
+const app = express()// .createServer()
+const http = require('http')
+const fs = require('fs')
+const QRCode = require('../lib')
+const canvasutil = require('canvasutil')
+const { createCanvas, loadImage } = require('canvas')
 
-var path = require('path')
+const path = require('path')
 
 // app.use(express.methodOverride())
 // app.use(express.bodyParser())
@@ -29,12 +29,12 @@ app.get('/', function (req, res) {
   })
 })
 
-var effectHandlers = {}
+const effectHandlers = {}
 
 app.get('/generate', function (req, res) {
-  var q = req.query || {}
+  const q = req.query || {}
 
-  var effect = q.effect || 'plain'
+  let effect = q.effect || 'plain'
   if (!effectHandlers[effect]) {
     effect = 'plain'
   }
@@ -48,7 +48,7 @@ app.get('/generate', function (req, res) {
         }
       })
     } else {
-      var msg = error.message + '\n' + error.stack
+      const msg = error.message + '\n' + error.stack
       res.header('Content-Type', 'text/plain')
       res.send(msg)
       console.error(msg)
@@ -72,28 +72,28 @@ effectHandlers.bacon = function (args, cb) {
 }
 
 effectHandlers.rounded = function (args, cb) {
-  var canvas = createCanvas(200, 200)
+  const canvas = createCanvas(200, 200)
   QRCode.toCanvas(canvas, args.text || '', function (err) {
     if (err) {
       cb(err, canvas)
       return
     }
 
-    var tpx = new canvasutil.PixelCore()
-    var luma709Only = canvasutil.conversionLib.luma709Only
-    var up = []
-    var down = []
-    var left = []
-    var right = []
-    var upPx
-    var downPx
-    var leftPx
-    var rightPx
-    var r
-    var t
-    var l
-    var d
-    var corner = 0
+    const tpx = new canvasutil.PixelCore()
+    const luma709Only = canvasutil.conversionLib.luma709Only
+    const up = []
+    const down = []
+    const left = []
+    const right = []
+    let upPx
+    let downPx
+    let leftPx
+    let rightPx
+    let r
+    let t
+    let l
+    let d
+    let corner = 0
 
     tpx.threshold = 100
 
@@ -166,16 +166,16 @@ effectHandlers.rounded = function (args, cb) {
 }
 
 effectHandlers.remoteImage = function (args, cb) {
-  var src = args.src
-  var domain
-  var uri
+  let src = args.src
+  let domain
+  let uri
 
   if (!src) {
     cb(new Error('src required'), null)
   } else {
     if (src.indexof('://') !== -1) {
       src = src.split('://').unshift()
-      var parts = src.split('/')
+      const parts = src.split('/')
 
       domain = parts.shift()
       uri = parts.join('/')
@@ -187,22 +187,22 @@ effectHandlers.remoteImage = function (args, cb) {
     return
   }
 
-  var options = {
+  const options = {
     host: domain,
     port: 80,
     path: uri,
     method: 'GET'
   }
 
-  var req = http.request(options, function (res) {
+  const req = http.request(options, function (res) {
     if (res.statusCode < 200 || res.statusCode > 299) {
       cb(new Error('http ' + res.statusCode + ' response code'), null)
       return
     }
 
     res.setEncoding('utf8')
 
-    var data = ''
+    let data = ''
     res.on('data', function (chunk) {
       data += chunk
       console.log('BODY: ' + chunk)
@@ -223,27 +223,27 @@ effectHandlers.remoteImage = function (args, cb) {
 
 effectHandlers.image = function (args, cb) {
   loadImage(args.src || '').then((img) => {
-    var convert = canvasutil.conversionLib
-    var canvas = createCanvas(200, 200)
+    const convert = canvasutil.conversionLib
+    const canvas = createCanvas(200, 200)
     QRCode.toCanvas(canvas, args.text || '', function (err) {
       if (err) {
         cb(err, false)
         return
       }
 
-      var codeCtx = canvas.getContext('2d')
-      var frame = codeCtx.getImageData(0, 0, canvas.width, canvas.width)
-      var tpx = new canvasutil.PixelCore()
-      var baconCanvas = createCanvas(canvas.width, canvas.width)
-      var ctx = baconCanvas.getContext('2d')
-      var topThreshold = args.darkThreshold || 25
-      var bottomThreshold = args.lightThreshold || 75
+      const codeCtx = canvas.getContext('2d')
+      const frame = codeCtx.getImageData(0, 0, canvas.width, canvas.width)
+      const tpx = new canvasutil.PixelCore()
+      const baconCanvas = createCanvas(canvas.width, canvas.width)
+      const ctx = baconCanvas.getContext('2d')
+      const topThreshold = args.darkThreshold || 25
+      const bottomThreshold = args.lightThreshold || 75
 
       tpx.threshold = 50
 
       // scale image
-      var w = canvas.width
-      var h = canvas.height
+      let w = canvas.width
+      let h = canvas.height
 
       if (img.width > img.height) {
         w = w * (canvas.height / h)
@@ -256,10 +256,10 @@ effectHandlers.image = function (args, cb) {
 
       try {
         tpx.iterate(baconCanvas, function (px, i, l, pixels, w, h, pixelCore) {
-          var luma = (0.2125 * px.r + 0.7154 * px.g + 0.0721 * px.b)
-          var codeLuma = convert.luma709Only(frame.data[i * 4], frame.data[i * 4 + 1], frame.data[i * 4 + 2])
-          var yuv
-          var rgb
+          const luma = (0.2125 * px.r + 0.7154 * px.g + 0.0721 * px.b)
+          const codeLuma = convert.luma709Only(frame.data[i * 4], frame.data[i * 4 + 1], frame.data[i * 4 + 2])
+          let yuv
+          let rgb
 
           if (codeLuma > pixelCore.threshold) {
             if (luma < bottomThreshold) {
@@ -296,8 +296,8 @@ effectHandlers.image = function (args, cb) {
 }
 
 effectHandlers.plain = function (args, cb) {
-  var canvas = createCanvas(200, 200)
-  var text = args.text || ''
+  const canvas = createCanvas(200, 200)
+  const text = args.text || ''
   QRCode.toCanvas(canvas, text || '', function (err) {
     cb(err, canvas)
   })

examples/save.js

@@ -1,6 +1,6 @@
-var QRCode = require('../lib')
+const QRCode = require('../lib')
 
-var path = './tmp.png'
+const path = './tmp.png'
 QRCode.toFile(path, 'life of the party bros', {
   color: {
     dark: '#00F', // Blue modules

examples/server.js

@@ -1,10 +1,10 @@
-var QRCode = require('../lib')
-var http = require('http')
+const QRCode = require('../lib')
+const http = require('http')
 
 function testQRCode (req, res) {
   res.writeHead(200, { 'Content-Type': 'text/html' })
 
-  var jungleBook = "The moonlight was blocked out of the mouth of the cave, for Shere Khan's\n" +
+  const jungleBook = "The moonlight was blocked out of the mouth of the cave, for Shere Khan's\n" +
   'great square head and shoulders were thrust into the entrance. Tabaqui,\n' +
   'behind him, was squeaking: "My lord, my lord, it went in here!"\n' +
   '\n' +

helper/to-sjis.js

@@ -1,4 +1,4 @@
-var SJIS_UTF8 = [
+const SJIS_UTF8 = [
   [0x8140, '　、。，．・：；？！゛゜´｀¨＾￣＿ヽヾゝゞ〃仝々〆〇ー―‐／＼～∥｜…‥‘’“”（）〔〕［］｛｝〈〉《》「」『』【】＋－±×'],
   [0x8180, '÷＝≠＜＞'],
   [0x818f, '￥＄￠￡％＃＆＊＠§☆★'],
@@ -89,10 +89,10 @@ var SJIS_UTF8 = [
 module.exports = function toSJIS (utf8Char) {
   if (!utf8Char || utf8Char === '') return
 
-  for (var i = 0; i < SJIS_UTF8.length; i++) {
-    var kanji = SJIS_UTF8[i][1]
+  for (let i = 0; i < SJIS_UTF8.length; i++) {
+    const kanji = SJIS_UTF8[i][1]
 
-    var posIndex = kanji.indexOf(utf8Char)
+    const posIndex = kanji.indexOf(utf8Char)
     if (posIndex >= 0) {
       return SJIS_UTF8[i][0] + posIndex
     }

lib/browser.js

@@ -1,14 +1,14 @@
 
-var canPromise = require('./can-promise')
+const canPromise = require('./can-promise')
 
-var QRCode = require('./core/qrcode')
-var CanvasRenderer = require('./renderer/canvas')
-var SvgRenderer = require('./renderer/svg-tag.js')
+const QRCode = require('./core/qrcode')
+const CanvasRenderer = require('./renderer/canvas')
+const SvgRenderer = require('./renderer/svg-tag.js')
 
 function renderCanvas (renderFunc, canvas, text, opts, cb) {
-  var args = [].slice.call(arguments, 1)
-  var argsNum = args.length
-  var isLastArgCb = typeof args[argsNum - 1] === 'function'
+  const args = [].slice.call(arguments, 1)
+  const argsNum = args.length
+  const isLastArgCb = typeof args[argsNum - 1] === 'function'
 
   if (!isLastArgCb && !canPromise()) {
     throw new Error('Callback required as last argument')
@@ -50,7 +50,7 @@ function renderCanvas (renderFunc, canvas, text, opts, cb) {
 
     return new Promise(function (resolve, reject) {
       try {
-        var data = QRCode.create(text, opts)
+        const data = QRCode.create(text, opts)
         resolve(renderFunc(data, canvas, opts))
       } catch (e) {
         reject(e)
@@ -59,7 +59,7 @@ function renderCanvas (renderFunc, canvas, text, opts, cb) {
   }
 
   try {
-    var data = QRCode.create(text, opts)
+    const data = QRCode.create(text, opts)
     cb(null, renderFunc(data, canvas, opts))
   } catch (e) {
     cb(e)

lib/core/alignment-pattern.js

@@ -8,7 +8,7 @@
  * and their number depends on the symbol version.
  */
 
-var getSymbolSize = require('./utils').getSymbolSize
+const getSymbolSize = require('./utils').getSymbolSize
 
 /**
  * Calculate the row/column coordinates of the center module of each alignment pattern
@@ -27,12 +27,12 @@ var getSymbolSize = require('./utils').getSymbolSize
 exports.getRowColCoords = function getRowColCoords (version) {
   if (version === 1) return []
 
-  var posCount = Math.floor(version / 7) + 2
-  var size = getSymbolSize(version)
-  var intervals = size === 145 ? 26 : Math.ceil((size - 13) / (2 * posCount - 2)) * 2
-  var positions = [size - 7] // Last coord is always (size - 7)
+  const posCount = Math.floor(version / 7) + 2
+  const size = getSymbolSize(version)
+  const intervals = size === 145 ? 26 : Math.ceil((size - 13) / (2 * posCount - 2)) * 2
+  const positions = [size - 7] // Last coord is always (size - 7)
 
-  for (var i = 1; i < posCount - 1; i++) {
+  for (let i = 1; i < posCount - 1; i++) {
     positions[i] = positions[i - 1] - intervals
   }
 
@@ -55,19 +55,19 @@ exports.getRowColCoords = function getRowColCoords (version) {
  * Note that the coordinates (6,6), (6,38), (38,6) are occupied by finder patterns
  * and are not therefore used for alignment patterns.
  *
- * var pos = getPositions(7)
+ * let pos = getPositions(7)
  * // [[6,22], [22,6], [22,22], [22,38], [38,22], [38,38]]
  *
  * @param  {Number} version QR Code version
  * @return {Array}          Array of coordinates
  */
 exports.getPositions = function getPositions (version) {
-  var coords = []
-  var pos = exports.getRowColCoords(version)
-  var posLength = pos.length
+  const coords = []
+  const pos = exports.getRowColCoords(version)
+  const posLength = pos.length
 
-  for (var i = 0; i < posLength; i++) {
-    for (var j = 0; j < posLength; j++) {
+  for (let i = 0; i < posLength; i++) {
+    for (let j = 0; j < posLength; j++) {
       // Skip if position is occupied by finder patterns
       if ((i === 0 && j === 0) || // top-left
           (i === 0 && j === posLength - 1) || // bottom-left

lib/core/alphanumeric-data.js

@@ -1,4 +1,4 @@
-var Mode = require('./mode')
+const Mode = require('./mode')
 
 /**
  * Array of characters available in alphanumeric mode
@@ -9,7 +9,7 @@ var Mode = require('./mode')
  *
  * @type {Array}
  */
-var ALPHA_NUM_CHARS = [
+const ALPHA_NUM_CHARS = [
   '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
   'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
   'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
@@ -34,13 +34,13 @@ AlphanumericData.prototype.getBitsLength = function getBitsLength () {
 }
 
 AlphanumericData.prototype.write = function write (bitBuffer) {
-  var i
+  let i
 
   // Input data characters are divided into groups of two characters
   // and encoded as 11-bit binary codes.
   for (i = 0; i + 2 <= this.data.length; i += 2) {
     // The character value of the first character is multiplied by 45
-    var value = ALPHA_NUM_CHARS.indexOf(this.data[i]) * 45
+    let value = ALPHA_NUM_CHARS.indexOf(this.data[i]) * 45
 
     // The character value of the second digit is added to the product
     value += ALPHA_NUM_CHARS.indexOf(this.data[i + 1])

lib/core/bit-buffer.js

@@ -6,12 +6,12 @@ function BitBuffer () {
 BitBuffer.prototype = {
 
   get: function (index) {
-    var bufIndex = Math.floor(index / 8)
+    const bufIndex = Math.floor(index / 8)
     return ((this.buffer[bufIndex] >>> (7 - index % 8)) & 1) === 1
   },
 
   put: function (num, length) {
-    for (var i = 0; i < length; i++) {
+    for (let i = 0; i < length; i++) {
       this.putBit(((num >>> (length - i - 1)) & 1) === 1)
     }
   },
@@ -21,7 +21,7 @@ BitBuffer.prototype = {
   },
 
   putBit: function (bit) {
-    var bufIndex = Math.floor(this.length / 8)
+    const bufIndex = Math.floor(this.length / 8)
     if (this.buffer.length <= bufIndex) {
       this.buffer.push(0)
     }