Better try and catch messages
#1509
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felixmulder
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| handler match { | ||
| case Block(Nil, EmptyTree) => syntaxError( | ||
| "`catch` block does not contain a valid expression, try adding a case like - `case t: Throwable =>` to the block", |
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People should not use Throwable unless they know what they're doing, I would suggest case e: Exception => instead
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Even better: case scala.util.control.NonFatal(e) =>
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I'm not against that, but do we really want to recommend people to do that by default? NonFatal will catch StackOverflowException among other things
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It doesn't:
scala> try { throw new StackOverflowError } catch { case scala.util.control.NonFatal(e) => println("I caught you!") }
java.lang.StackOverflowError
at .liftedTree1$1(<console>:8)
... 33 elidedNonFatal is precisely meant as a good default, to catch all the things you should catch, and none of those you shouldn't.
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Ha you're right, I googled to find the doc and didn't realize I was looking at the 2.9 version :) scala-lang.org/api/2.9.3/scala/util/control/NonFatal$.html
felixmulder
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| @@ -0,0 +1,3 @@ | |||
| object Test { | |||
| try {} catch {} // error: `catch` block does not contain a valid expression, try adding a case like - `case t: Throwable =>` to the block | |||
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Done - not sure why github is displaying the old code here...
felixmulder
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Fixes #1446, and allows a
trywithout acatchorfinallyas per the spec.