问题
I am wondering if anyone knows why some people define global variables that are set to functions vs just defining a global function name. For example:
var foo = function() { alert('hello!'); }
instead of
function foo() { alert('hello!'); }
Wouldn't the second method be better since there is a chance something might overwrite the first variable and you would lose the function? Does this have anything to do with extending objects? Are there performance concerns?
来源：https://stackoverflow.com/questions/3435709/why-are-functions-in-javascript-set-to-global-variables-instead-of-plain-functio