2022-06-30 08:50:09 +00:00
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#![warn(clippy::manual_find)]
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2022-10-06 07:44:38 +00:00
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#![allow(unused)]
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#![allow(clippy::needless_return, clippy::uninlined_format_args)]
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2022-06-30 08:50:09 +00:00
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use std::collections::HashMap;
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const ARRAY: &[u32; 5] = &[2, 7, 1, 9, 3];
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fn lookup(n: u32) -> Option<u32> {
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ARRAY.iter().find(|&&v| v == n).copied()
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}
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fn with_pat(arr: Vec<(u32, u32)>) -> Option<u32> {
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arr.into_iter().map(|(a, _)| a).find(|&a| a % 2 == 0)
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}
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struct Data {
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name: String,
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is_true: bool,
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}
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fn with_struct(arr: Vec<Data>) -> Option<Data> {
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arr.into_iter().find(|el| el.name.len() == 10)
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}
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struct Tuple(usize, usize);
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fn with_tuple_struct(arr: Vec<Tuple>) -> Option<usize> {
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arr.into_iter().map(|Tuple(a, _)| a).find(|&a| a >= 3)
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}
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struct A;
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impl A {
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fn should_keep(&self) -> bool {
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true
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}
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}
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fn with_method_call(arr: Vec<A>) -> Option<A> {
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arr.into_iter().find(|el| el.should_keep())
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}
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fn with_closure(arr: Vec<u32>) -> Option<u32> {
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let f = |el: u32| -> u32 { el + 10 };
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arr.into_iter().find(|&el| f(el) == 20)
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}
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fn with_closure2(arr: HashMap<String, i32>) -> Option<i32> {
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let f = |el: i32| -> bool { el == 10 };
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arr.values().find(|&&el| f(el)).copied()
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}
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fn with_bool(arr: Vec<Data>) -> Option<Data> {
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arr.into_iter().find(|el| el.is_true)
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}
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fn with_side_effects(arr: Vec<u32>) -> Option<u32> {
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for v in arr {
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if v == 1 {
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println!("side effect");
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return Some(v);
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}
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}
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None
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}
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fn with_else(arr: Vec<u32>) -> Option<u32> {
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for el in arr {
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if el % 2 == 0 {
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return Some(el);
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} else {
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println!("{}", el);
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}
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}
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None
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}
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fn tuple_with_ref(v: [(u8, &u8); 3]) -> Option<u8> {
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v.into_iter().map(|(_, &x)| x).find(|&x| x > 10)
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}
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fn ref_to_tuple_with_ref(v: &[(u8, &u8)]) -> Option<u8> {
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v.iter().map(|&(_, &x)| x).find(|&x| x > 10)
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}
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fn explicit_ret(arr: Vec<i32>) -> Option<i32> {
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arr.into_iter().find(|&x| x >= 5)
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}
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fn plus_one(a: i32) -> Option<i32> {
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Some(a + 1)
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}
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fn fn_instead_of_some(a: &[i32]) -> Option<i32> {
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for &x in a {
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if x == 1 {
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return plus_one(x);
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}
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}
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None
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}
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fn for_in_condition(a: &[i32], b: bool) -> Option<i32> {
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if b {
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for &x in a {
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if x == 1 {
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return Some(x);
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}
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}
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}
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None
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}
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fn intermediate_statements(a: &[i32]) -> Option<i32> {
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for &x in a {
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if x == 1 {
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return Some(x);
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}
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}
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println!("side effect");
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None
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}
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fn mixed_binding_modes(arr: Vec<(i32, String)>) -> Option<i32> {
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for (x, mut s) in arr {
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if x == 1 && s.as_mut_str().len() == 2 {
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return Some(x);
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}
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}
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None
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}
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fn as_closure() {
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#[rustfmt::skip]
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let f = |arr: Vec<i32>| -> Option<i32> {
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arr.into_iter().find(|&x| x < 1)
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};
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}
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fn in_block(a: &[i32]) -> Option<i32> {
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let should_be_none = {
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for &x in a {
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if x == 1 {
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return Some(x);
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}
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}
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None
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};
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assert!(should_be_none.is_none());
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should_be_none
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}
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// Not handled yet
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fn mut_binding(v: Vec<String>) -> Option<String> {
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for mut s in v {
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if s.as_mut_str().len() > 1 {
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return Some(s);
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}
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}
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None
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}
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fn subpattern(v: Vec<[u32; 32]>) -> Option<[u32; 32]> {
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for a @ [first, ..] in v {
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if a[12] == first {
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return Some(a);
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}
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}
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None
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}
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fn two_bindings(v: Vec<(u8, u8)>) -> Option<u8> {
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for (a, n) in v {
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if a == n {
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return Some(a);
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}
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}
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None
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}
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fn main() {}
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