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'use strict';
var fnToStr = Function.prototype.toString;
var reflectApply = typeof Reflect === 'object' && Reflect !== null && Reflect.apply;
var badArrayLike;
var isCallableMarker;
if (typeof reflectApply === 'function' && typeof Object.defineProperty === 'function') {
try {
badArrayLike = Object.defineProperty({}, 'length', {
get: function () {
throw isCallableMarker;
}
});
isCallableMarker = {};
// eslint-disable-next-line no-throw-literal
reflectApply(function () { throw 42; }, null, badArrayLike);
} catch (_) {
if (_ !== isCallableMarker) {
reflectApply = null;
}
}
} else {
reflectApply = null;
}
var constructorRegex = /^\s*class\b/;
var isES6ClassFn = function isES6ClassFunction(value) {
try {
var fnStr = fnToStr.call(value);
return constructorRegex.test(fnStr);
} catch (e) {
return false; // not a function
}
};
var tryFunctionObject = function tryFunctionToStr(value) {
try {
if (isES6ClassFn(value)) { return false; }
fnToStr.call(value);
return true;
} catch (e) {
return false;
}
};
var toStr = Object.prototype.toString;
var fnClass = '[object Function]';
var genClass = '[object GeneratorFunction]';
var hasToStringTag = typeof Symbol === 'function' && typeof Symbol.toStringTag === 'symbol';
module.exports = reflectApply
? function isCallable(value) {
if (!value) { return false; }
if (typeof value !== 'function' && typeof value !== 'object') { return false; }
if (typeof value === 'function' && !value.prototype) { return true; }
try {
reflectApply(value, null, badArrayLike);
} catch (e) {
if (e !== isCallableMarker) { return false; }
}
return !isES6ClassFn(value);
}
: function isCallable(value) {
if (!value) { return false; }
if (typeof value !== 'function' && typeof value !== 'object') { return false; }
if (typeof value === 'function' && !value.prototype) { return true; }
if (hasToStringTag) { return tryFunctionObject(value); }
if (isES6ClassFn(value)) { return false; }
var strClass = toStr.call(value);
return strClass === fnClass || strClass === genClass;
};