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Language FAQ: update the entry on exceptions.
R=rsc, iant CC=golang-dev https://golang.org/cl/824045
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@ -282,20 +282,19 @@ This remains an open issue.
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<h3 id="exceptions">
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Why does Go not have exceptions?</h3>
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<p>
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Exceptions are a similar story. A number of designs for exceptions
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have been proposed but each adds significant complexity to the
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language and run-time. By their very nature, exceptions span functions and
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perhaps even goroutines; they have wide-ranging implications. There
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is also concern about the effect they would have on the
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libraries. They are, by definition, exceptional yet experience with
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other languages that support them show they have profound effect on
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library and interface specification. It would be nice to find a design
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that allows them to be truly exceptional without encouraging common
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errors to turn into special control flow that requires every programmer to
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compensate.
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We believe that coupling the usual idea of exceptions to a control
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structure, as in the <code>try-catch-finally</code> idiom, results in
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convoluted code. It also tends to encourage programmers to label
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too many ordinary errors, such as failing to open a file, as
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exceptional. And then the type system gets mixed in.
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</p>
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<p>
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Like generics, exceptions remain an open issue.
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Go takes a different approach. Instead of exceptions, it has couple
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of built-in functions to signal and recover from truly exceptional
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conditions. The recovery mechanism is executed only as part of a
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function's state being torn down after an error, which is sufficient
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to handle catastrophe but requires no extra control structures and,
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when used well, can result in clean error-handling code.
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</p>
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<h3 id="assertions">
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