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Because this is a theological conjecture, I think we're shocked by what is almost the heretical daring of what this brother has just said.
因为这是一个神学猜想,我想我们是被刚才大哥说的异常大胆的话震惊了。
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The exception is right there. It's an index error, that is it's trying to do something going beyond the range of what this thing could deal with.
但他事实上抛出一个异常，异常就在这里，这是一个下标错误,它是试图去取超出范围的元素造成的。
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I think there's actually a reason for this aberration.
我认为有一个原因能解释这种异常。
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OK, so far though, I've just shown you what happens inside a peace a code. It raises an exception. It goes to that accept clause. We don't have to use it just inside of one place.
好了，我已经给你们看了,代码内部发生了什么,它报了一个异常，然后就到了处理的片段,我们不该就在一个地方用它。
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Last thing to say is why would you want to have exceptions? Well, let's go back to that case of inputting a simple little floating point.
最后要讲的是为什么有异常处理？,回到输入一个简单的小浮点数的例子,如果我期望主要是。
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What does that say? It says if in the code up here I get an exception of that sort, I'm going to go to this place to handle it.
这意味着如果在代码中,我得到一个这样的异常,我能到这里来处理它。
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But if I say turn this into a float, ah it throws a value error exception.
它就会抛出一个值错误异常了，它会告诉我输入了一种错误的值。
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I'm much better having an exception get handled at the time of input than to let that prop -- that value rather propagate through a whole bunch of code until eventually it hits an error 17 calls later, and you have no clue where it came from.
不是我期望的格式,这时我最好有一个异常处理,而不是让其传下去,这个值传到代码的整个分支,最终会导致一个错误17调用的发生，并且你不知道这个错误是哪里来的。
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Right, so an exception then has this format that I can control as a programmer.
好的，所以一个异常会有这样的格式,我能把他当做一个程序员来控制。
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So it's not defined. But in fact, what this did was it threw an exception.
这是未定义，但实际上，这里做的就是抛出一个异常。
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That says it's in here. It's in this tri-block. It raised an exception, but it wasn't and I O error.
这在这里它是一个try程序块,它报出异常，但他不是io错误。
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An exception is called a name error exception.
一个被称作命名错误的异常。
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The format is the same. I'm going to ask for some input, and then I am going to use that procedure to check, is this the right type of value. And I'm trying to use that to do the coercion if you like. Same thing if it works, I'm going to skip that, if it not, it's going to throw the exception.
格式是一样的，我需要一些输入,然后我要用一个过程来检查,是否是正确的值,然后你就可以做强制转换了,如果能运行，那是一样的，我打算跳过这段，如果不正确，那就会抛出一个异常。
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When we're just interacting with idol, with the interactive editor or sorry, interactive environment if you like, that's what you expect. What's happening is that we're typing in something, an expression it doesn't know how to deal. It's raising the exception, but is this simply bubbling up at the top level saying you've got a problem.
就发生了其中之一是吧，当你在交互数据处理或者是在交互编辑器，抱歉，任何你喜欢的交互式环境中，你可能会遇到这些，如果你在输入什么内容,譬如一个它不知道怎么处理的表达式,它就会报一个异常,但这是否是简单的,把你遇到的问题冒到最顶层呢？
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That goes back to that idea of sort of discipline coding. It's easy to have assumptions about what you think are going to come into the program when you writ it. If you really know what they are use them as search, but if you think there's going to be some flexibility, you want to prevent the user getting trapped in a bad spot, and exceptions as a consequence are a good thing to use.
这又回到了规范编码的想法上来了,在你写代码的时候考虑,什么会进入你的代码的思考是简单的,如果你真的知道,他们是用他们来做搜索的,而你希望有一定的灵活性，你想要阻止用户,陷入一个艰难的境地,那么异常是非常实用的。
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