#![feature(plugin)] #![plugin(clippy)] #![allow(unused, needless_pass_by_value)] #![deny(map_entry)] use std::collections::{BTreeMap, HashMap}; use std::hash::Hash; fn foo() {} fn insert_if_absent0(m: &mut HashMap, k: K, v: V) { if !m.contains_key(&k) { m.insert(k, v); } } fn insert_if_absent1(m: &mut HashMap, k: K, v: V) { if !m.contains_key(&k) { foo(); m.insert(k, v); } } fn insert_if_absent2(m: &mut HashMap, k: K, v: V) { if !m.contains_key(&k) { m.insert(k, v) } else { None }; } fn insert_if_present2(m: &mut HashMap, k: K, v: V) { if m.contains_key(&k) { None } else { m.insert(k, v) }; } fn insert_if_absent3(m: &mut HashMap, k: K, v: V) { if !m.contains_key(&k) { foo(); m.insert(k, v) } else { None }; } fn insert_if_present3(m: &mut HashMap, k: K, v: V) { if m.contains_key(&k) { None } else { foo(); m.insert(k, v) }; } fn insert_in_btreemap(m: &mut BTreeMap, k: K, v: V) { if !m.contains_key(&k) { foo(); m.insert(k, v) } else { None }; } fn insert_other_if_absent(m: &mut HashMap, k: K, o: K, v: V) { if !m.contains_key(&k) { m.insert(o, v); } } fn main() { }