ECMA4

Mozilla Firefox Thunderbird の拡張あれこれ-MEMO（2007年11月-4）経由print "Me" ECMAScript 4, the fourth system syndrome

一番最後。

ECMAScript 4 seems cool, I want to use a lot of those things (yay for multi method dispatch!), but maybe it is changing the language a little bit too much .

How many of the current user of ES in one of its incarnations have ever heard of product types? Will they grasp at once the logic behind the subtyping relation between functions, with all that covariant and contravariant stuff? Will they need it at all?

ぜんぜん聞いたことないです。