2019-08-15 03:53:11 +00:00
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// run-rustfix
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#![deny(clippy::option_and_then_some)]
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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;
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let _ = x.map(|o| 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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2019-08-19 05:41:47 +00:00
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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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