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