26 lines
734 B
Rust
26 lines
734 B
Rust
#![deny(clippy::bind_instead_of_map)]
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#![allow(clippy::uninlined_format_args)]
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// need a main anyway, use it get rid of unused warnings too
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pub fn main() {
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let x = Some(5);
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// the easiest cases
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let _ = x.and_then(Some);
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let _ = x.and_then(|o| Some(o + 1));
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// and an easy counter-example
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let _ = x.and_then(|o| if o < 32 { Some(o) } else { None });
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// Different type
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let x: Result<u32, &str> = Ok(1);
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let _ = x.and_then(Ok);
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}
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pub fn foo() -> Option<String> {
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let x = Some(String::from("hello"));
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Some("hello".to_owned()).and_then(|s| Some(format!("{}{}", s, x?)))
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}
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pub fn example2(x: bool) -> Option<&'static str> {
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Some("a").and_then(|s| Some(if x { s } else { return None }))
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}
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