我看着MvcContrib网格组件,我很着迷,但同时又被网格语法中使用的语法技巧所排斥:
.Attributes(style => "width:100%")
上面的语法将生成的HTML的样式属性设置为width:100%。如果你注意的话,'style'并没有被指定。它是从表达式中参数的名称推导出来的!我必须深入研究这个问题,找到“魔法”发生的地方:
Hash(params Func<object, TValue>[] hash)
{
foreach (var func in hash)
{
Add(func.Method.GetParameters()[0].Name, func(null));
}
}
因此,代码确实使用了正式的、编译时的参数名称来创建属性名称-值对的字典。生成的语法结构确实非常具有表现力,但同时也非常危险。
lambda表达式的一般用法允许替换所使用的名称而不产生副作用。我在一本书上看到一个例子,上面写着收藏。我知道我可以在我的代码集合中写。ForEach(log => fire。burn (log))它的意思是一样的。但是使用这里的MvcContrib Grid语法,我突然发现代码可以根据我为变量选择的名称主动查找并做出决定!
那么这是c# 3.5/4.0社区和lambda表达式爱好者的普遍做法吗?还是说,我不应该担心一个流氓的诡计特立独行?
All this ranting about "horridness" is a bunch of long-time c# guys overreacting (and I'm a long-time C# programmer and still a very big fan of the language). There's nothing horrible about this syntax. It is merely an attempt to make the syntax look more like what you're trying to express. The less "noise" there is in the syntax for something, the easier the programmer can understand it. Decreasing the noise in one line of code only helps a little, but let that build up across more and more code, and it turns out to be a substantial benefit.
This is an attempt by the author to strive for the same benefits that DSL's give you -- when the code just "looks like" what you're trying to say, you've reached a magical place. You can debate whether this is good for interop, or whether it is enough nicer than anonymous methods to justify some of the "complexity" cost. Fair enough ... so in your project you should make the right choice of whether to use this kind of syntax. But still ... this is a clever attempt by a programmer to do what, at the end of the day, we're all trying to do (whether we realize it or not). And what we're all trying to do, is this: "Tell the computer what we want it to do in language that is as close as possible to how we think about what want it to do."
使软件更易于维护、更准确的关键在于,我们能够更接近于用我们内心认为的方式向计算机表达指令。
编辑:我曾经说过“使软件更具可维护性和准确性的关键”,这是一种疯狂的天真和夸张的独角兽观点。我把它改成了“钥匙”。