45 lines
847 B
Markdown
45 lines
847 B
Markdown
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# Try expressions
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```thp
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fun get_value() -> Result[Int, String] { ... }
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// treating errors as normal enums
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val result = match get_value()
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case Ok(result) { result }
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case Err(error) { return error }
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// get the value if Ok, otherwise re-throw
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val result = try get_value()
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// get the value if Ok, return a new value otherwise
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val result = try get_value() return Err("new error")
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// get the value if Ok, assign a new value otherwise
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Int result = try get_value() else 20
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// get the value if Ok, otherwise run block with the error value
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val result = try get_value()
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with error
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{
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// handle error
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}
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fun throws_exception() -> Result[Int, MyException|MyOtherException] { ... }
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val result = try throws_exception() catch
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case MyException(e)
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{
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// deal with MyException
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}
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case MyOtherException(e)
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{
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// deal with MyOtherException
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}
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```
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