diff --git a/src/cldr/currency.js b/src/cldr/currency.js
index fe26d1fe..fab71fce 100644
--- a/src/cldr/currency.js
+++ b/src/cldr/currency.js
@@ -114,7 +114,7 @@ export function currencyDisplay(locale, options) {
     if (currencyDisplay === SYMBOL) {
         result = currencyInfo["symbol-alt-narrow"] || currencyInfo[SYMBOL];
     } else {
-        if (typeof value === undefined || value !== 1) {
+        if (typeof value === "undefined" || value !== 1) {
             result = currencyInfo["displayName-count-other"];
         } else {
             result = currencyInfo["displayName-count-one"];
diff --git a/src/dates/parse-date.js b/src/dates/parse-date.js
index a2763a26..7a2ea9d4 100644
--- a/src/dates/parse-date.js
+++ b/src/dates/parse-date.js
@@ -7,7 +7,7 @@ import datePattern from './date-pattern';
 import round from '../common/round';
 import isDate from '../common/is-date';
 
-const timeZoneOffsetRegExp = /([+|\-]\d{1,2})(:?)(\d{2})?/;
+const timeZoneOffsetRegExp = /([+|-]\d{1,2})(:?)(\d{2})?/;
 const dateRegExp = /^\/Date\((.*?)\)\/$/;
 const offsetRegExp = /[+-]\d*/;
 const numberRegExp = {
diff --git a/src/format.js b/src/format.js
index 25459801..2ec8a29f 100644
--- a/src/format.js
+++ b/src/format.js
@@ -4,7 +4,7 @@ import { EMPTY } from './common/constants';
 import isDate from './common/is-date';
 import isNumber from './common/is-number';
 
-const formatRegExp = /\{(\d+)(:[^\}]+)?\}/g;
+const formatRegExp = /\{(\d+)(:[^}]+)?\}/g;
 
 export function toString(value, format, locale) {
     if (format) {
diff --git a/src/numbers/custom-number-format.js b/src/numbers/custom-number-format.js
index 2343b160..6ade8871 100644
--- a/src/numbers/custom-number-format.js
+++ b/src/numbers/custom-number-format.js
@@ -9,7 +9,7 @@ const ZERO = "0";
 
 const trailingZerosRegExp = /(\.(?:[0-9]*[1-9])?)0+$/g;
 const trailingPointRegExp = /\.$/;
-const commaRegExp = /\,/g;
+const commaRegExp = /,/g;
 
 function trimTrailingZeros(value, lastZero) {
     let trimRegex;
diff --git a/src/numbers/parse-number.js b/src/numbers/parse-number.js
index 99c97a10..9fe00bff 100644
--- a/src/numbers/parse-number.js
+++ b/src/numbers/parse-number.js
@@ -6,7 +6,7 @@ import isCurrencyStyle from './is-currency-style';
 import formatOptions from './format-options';
 import isString from '../common/is-string';
 
-const exponentRegExp = /[eE][\-+]?[0-9]+/;
+const exponentRegExp = /[eE][-+]?[0-9]+/;
 const nonBreakingSpaceRegExp = /\u00A0/g;
 
 function cleanNegativePattern(number, patterns) {