aaac7fed
 liuqimichale
add
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'use strict';
var has = require('has');
var regexExec = RegExp.prototype.exec;
var gOPD = Object.getOwnPropertyDescriptor;
var tryRegexExecCall = function tryRegexExec(value) {
try {
var lastIndex = value.lastIndex;
value.lastIndex = 0;
regexExec.call(value);
return true;
} catch (e) {
return false;
} finally {
value.lastIndex = lastIndex;
}
};
var toStr = Object.prototype.toString;
var regexClass = '[object RegExp]';
var hasToStringTag = typeof Symbol === 'function' && typeof Symbol.toStringTag === 'symbol';
module.exports = function isRegex(value) {
if (!value || typeof value !== 'object') {
return false;
}
if (!hasToStringTag) {
return toStr.call(value) === regexClass;
}
var descriptor = gOPD(value, 'lastIndex');
var hasLastIndexDataProperty = descriptor && has(descriptor, 'value');
if (!hasLastIndexDataProperty) {
return false;
}
return tryRegexExecCall(value);
};
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