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use std::ops::ControlFlow;
fn result_to_result() -> Result<u64, u8> {
Ok(Err(123_i32)?)
//~^ ERROR `?` couldn't convert the error to `u8`
}
fn option_to_result() -> Result<u64, String> {
Some(3)?;
//~^ ERROR the `?` operator can only be used on `Result`s, not `Option`s, in a function that returns `Result`
Ok(10)
}
fn control_flow_to_result() -> Result<u64, String> {
Ok(ControlFlow::Break(123)?)
//~^ ERROR the `?` operator can only be used on `Result`s in a function that returns `Result`
}
fn result_to_option() -> Option<u16> {
Some(Err("hello")?)
//~^ ERROR the `?` operator can only be used on `Option`s, not `Result`s, in a function that returns `Option`
}
fn control_flow_to_option() -> Option<u64> {
Some(ControlFlow::Break(123)?)
//~^ ERROR the `?` operator can only be used on `Option`s in a function that returns `Option`
}
fn result_to_control_flow() -> ControlFlow<String> {
ControlFlow::Continue(Err("hello")?)
//~^ ERROR the `?` operator can only be used on `ControlFlow`s in a function that returns `ControlFlow`
}
fn option_to_control_flow() -> ControlFlow<u64> {
Some(3)?;
//~^ ERROR the `?` operator can only be used on `ControlFlow`s in a function that returns `ControlFlow`
ControlFlow::Break(10)
}
fn control_flow_to_control_flow() -> ControlFlow<i64> {
ControlFlow::Break(4_u8)?;
//~^ ERROR the `?` operator in a function that returns `ControlFlow<B, _>` can only be used on other `ControlFlow<B, _>`s
ControlFlow::Continue(())
}
fn main() {}
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