62 lines
1.6 KiB
Rust
62 lines
1.6 KiB
Rust
#![deny(clippy::bind_instead_of_map)]
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#![allow(clippy::blocks_in_if_conditions)]
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pub fn main() {
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let _ = Some("42").and_then(|s| if s.len() < 42 { Some(0) } else { Some(s.len()) });
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let _ = Some("42").and_then(|s| if s.len() < 42 { None } else { Some(s.len()) });
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let _ = Ok::<_, ()>("42").and_then(|s| if s.len() < 42 { Ok(0) } else { Ok(s.len()) });
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let _ = Ok::<_, ()>("42").and_then(|s| if s.len() < 42 { Err(()) } else { Ok(s.len()) });
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let _ = Err::<(), _>("42").or_else(|s| if s.len() < 42 { Err(s.len() + 20) } else { Err(s.len()) });
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let _ = Err::<(), _>("42").or_else(|s| if s.len() < 42 { Ok(()) } else { Err(s.len()) });
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hard_example();
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macro_example();
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}
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fn hard_example() {
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Some("42").and_then(|s| {
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if {
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if s == "43" {
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return Some(43);
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}
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s == "42"
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} {
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return Some(45);
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}
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match s.len() {
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10 => Some(2),
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20 => {
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if foo() {
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return {
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if foo() {
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return Some(20);
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}
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println!("foo");
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Some(3)
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};
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}
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Some(20)
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},
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40 => Some(30),
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_ => Some(1),
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}
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});
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}
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fn foo() -> bool {
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true
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}
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macro_rules! m {
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() => {
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Some(10)
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};
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}
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fn macro_example() {
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let _ = Some("").and_then(|s| if s.len() == 20 { m!() } else { Some(20) });
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let _ = Some("").and_then(|s| if s.len() == 20 { Some(m!()) } else { Some(Some(20)) });
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}
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