blocks|key|522595|text|可以，您可以查看scala.util.control.Exception对象。特别是allCatch函数。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|522596|entityMap|0|LINK|mutability|MUTABLE|url|http://www.scala-lang.org/api/current/index.html#scala.util.control.Exception%2524^0|8|S|16|8|8|S|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@$9|O|A|P|B|C]|$9|Q|A|R|B|C]]|D|@$9|S|A|T|1|U]]|E|$]]|$1|F|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|G|$H|$5|I|J|K|E|$L|M]]]]

Yes, you can take a look to the <a href="http://www.scala-lang.org/api/current/index.html#scala.util.control.Exception%24" rel="nofollow"><code>scala.util.control.Exception</code></a> object. Especially, the <code>allCatch</code> function.

blocks|key|522661|text|使用scala.util.control.Exception|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|522662|import+scala.util.control.Exception._

allCatch+opt+f|code-block|syntax|javascript|522663|你可以让它变得更复杂。例如，要仅捕获算术异常并检索异常：|522664|scala>+catching(classOf[ArithmeticException])+either+(2+/+0)
res5:+Either[Throwable,Int]+=+Left(java.lang.ArithmeticException:+/+by+zero)|522665|entityMap|0|LINK|mutability|MUTABLE|url|http://www.scala-lang.org/api/current/index.html#scala.util.control.Exception$^0|2|S|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]]]

Use <a href="http://www.scala-lang.org/api/current/index.html#scala.util.control.Exception$" rel="nofollow noreferrer">scala.util.control.Exception</a>:

<pre><code>import scala.util.control.Exception._

allCatch opt f
</code></pre>

And you can make it more sophisticated. For example, to catch only arithmetic exceptions and retrieve the exception:

<pre><code>scala&gt; catching(classOf[ArithmeticException]) either (2 / 0)
res5: Either[Throwable,Int] = Left(java.lang.ArithmeticException: / by zero)
</code></pre>

blocks|key|739179|text|Scalaz提供了类似于Either的Validation[%2BE,+%2BA]。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|739180|val+result:+Validation[Throwable,+Something]+=+...

result+match+{
++case+Success(x)+=>+...
++case+Failure(x)+=>+...
}|code-block|syntax|javascript|739181|entityMap|0|LINK|mutability|MUTABLE|url|http://scalaz.googlecode.com/svn/continuous/latest/browse.sxr/scalaz/Validation.scala.html#17846^0|C|6|J|I|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@$9|V|A|W|1|X]]|E|$]]|$1|F|3|G|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

Scalaz provides <a href="http://scalaz.googlecode.com/svn/continuous/latest/browse.sxr/scalaz/Validation.scala.html#17846" rel="nofollow">Validation[+E, +A]</a> which is similar to <code>Either</code>.

<pre><code>val result: Validation[Throwable, Something] = ...

result match {
 case Success(x) =&gt; ...
 case Failure(x) =&gt; ...
}
</code></pre>

blocks|key|739221|text|从Scala2.10开始，您可以在scala.util.Try中运行代码(例如工厂方法)，然后使用toOption对其进行转换|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|739222|import+scala.util.Try
Try("foo".toInt).toOption++//+None
Try("7".toInt).toOption++++//+Some(7)|code-block|syntax|javascript|739223|或者翻译成您的原始示例：|739224|val+id:+Option[UUID]+=+Try(UUID.fromString("this+will+produce+None")).toOption|739225|entityMap|0|LINK|mutability|MUTABLE|url|http://www.scala-lang.org/api/current/index.html#scala.util.Try^0|1D|8|H|E|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@$9|Z|A|10|1|11]]|E|$]]|$1|F|3|G|5|H|7|12|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|13|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|14|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|15|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]]]

As of scala 2.10, you can run your code (e.g. factory method) in a <a href="http://www.scala-lang.org/api/current/index.html#scala.util.Try">scala.util.Try</a> and then convert it with <code>toOption</code>:

<pre><code>import scala.util.Try
Try("foo".toInt).toOption // None
Try("7".toInt).toOption // Some(7)
</code></pre>

Or translated to your original example:

<pre><code>val id: Option[UUID] = Try(UUID.fromString("this will produce None")).toOption
</code></pre>

blocks|key|522849|text|在现代计算机中，我使用基于信令和非信令NaNs的模式。NaN的意思是非数字。除以零(fp)将创建NaN。sNaNs抛出异常，仅提供非信令NaN作为结果，未来对结果的任何计算也会生成NaN。Evaluate是信令，TryEvaluate是非信令。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|522850|这里，Ctx=ContextI，R是保存函数输入I、resultR和异常的上下文块。所有这些都是选项。上下文上的update方法是copy-update。不是一个变异的更新。超特征只评估一个或多个函数，将更新后的上下文传递给下一个函数。如果存在异常(跳过求值)，则主evaluate函数返回上下文。ContextI，R具有将(I=>R)转换为(ContextI，R=>ContextI，R)的函数。因此，普通函数可以很容易地转换为基于上下文的函数。|522851|如您所见，代码不多。这些特征只是在我的实用程序包中，消费者几乎不需要代码就可以使用它们。使用库增加了相关工作的大量开销。|522852|我在我的所有解析器中都使用它。基于X路径的解析器只调用子解析器的序列。因此，使用evaluate(Seq)方法。注意:我不喜欢方法。我倾向于在我能使用的地方使用函数。|522853|哦，我想我上次发了垃圾邮件。以下是github的参考资料。https://github.com/tyohDeveloper/acme/tree/master/src/acme/util|offset|length|522854|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/tyohDeveloper/acme/tree/master/src/acme/util^0|0|0|0|0|T|1R|0|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|U|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|V|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|W|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|X|8|@]|9|@$J|Y|K|Z|1|10]]|A|$]]|$1|L|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|M|$N|$5|O|P|Q|A|$R|S]]]]

I use a pattern based on signaling and non-signally NaNs in modern computers. NaN means non-a-number. Division by zero (fp) creates a NaN. sNaNs throw exceptions, non-signaling NaNs are just provided as a result, any future computation on the result also generates a NaN. Evaluate is signalling, TryEvaluate is non-signaling.

Here, Ctx=Context[I,R] is a context block that holds the function's input [I], result[R], and an exception. All are Options. The update method on the context is a copy-update. Not a mutating update. The super-trait just evaluates one or more functions, passing the updated context to the next function. The main evaluate function returns the context if an exception is held (skipping the evaluation). Context[I,R] has a function that translates a (I=>R) into a (Context[I,R]=>Context[I,R]). So a normal function can easily be converted into a context based function. 

As you can see, there isn't much code. The traits are just in my utility package and can be used with almost no code by the consumer. Using a library adds to much overhead for the work involved. 

I use this for all of my parsers. X-Path based parsers just call a sequence of sub-parsers. Hence the evaluate(Seq) method. Note: I dislike methods. I tend to use functions where I can.

Oops, I think I posted garbage the last time. Here is a github reference.
<a href="https://github.com/tyohDeveloper/acme/tree/master/src/acme/util" rel="nofollow noreferrer">https://github.com/tyohDeveloper/acme/tree/master/src/acme/util</a>

This is basically to wrap java factory methods which throw exceptions if the item can't be created based on the inputs. I'm looking for something in the base library like:

<pre><code> def exceptionToOption[A](f: =&gt; A):Option[A] ={
 try{
 Some(f)}
 catch{
 case e:Exception =&gt; None}
 }
</code></pre>

Usage:

<pre><code>val id:Option[UUID] = exceptionToOption(UUID.fromString("this will produce None"))
</code></pre>

I know I can write my own but I want to check I am not re-inventing the wheel.

In Scala, is there a pre-existing library function for converting exceptions to Options?

这基本上是包装java工厂方法，如果不能基于输入创建项，这些方法就会抛出异常。我在基础库中查找类似以下内容： def exceptionToOption[A](f: => A):Option[A] ={    try{      Some(f)}    catch{      case e:Exception => N...

问在Scala中，是否有一个预先存在的库函数用于将异常转换为选项？
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问在Scala中，是否有一个预先存在的库函数用于将异常转换为选项？
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