forked from zhurui/management
32 lines
608 B
JavaScript
32 lines
608 B
JavaScript
'use strict';
|
|
module.exports = function (fn, errMsg) {
|
|
if (typeof fn !== 'function') {
|
|
throw new TypeError('Expected a function');
|
|
}
|
|
|
|
var ret;
|
|
var called = false;
|
|
var fnName = fn.displayName || fn.name || (/function ([^\(]+)/.exec(fn.toString()) || [])[1];
|
|
|
|
var onetime = function () {
|
|
if (called) {
|
|
if (errMsg === true) {
|
|
fnName = fnName ? fnName + '()' : 'Function';
|
|
throw new Error(fnName + ' can only be called once.');
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
called = true;
|
|
ret = fn.apply(this, arguments);
|
|
fn = null;
|
|
|
|
return ret;
|
|
};
|
|
|
|
onetime.displayName = fnName;
|
|
|
|
return onetime;
|
|
};
|