2 Checks for calls to `.or(foo(..))`, `.unwrap_or(foo(..))`,
3 `.or_insert(foo(..))` etc., and suggests to use `.or_else(|| foo(..))`,
4 `.unwrap_or_else(|| foo(..))`, `.unwrap_or_default()` or `.or_default()`
8 The function will always be called and potentially
9 allocate an object acting as the default.
12 If the function has side-effects, not calling it will
13 change the semantic of the program, but you shouldn't rely on that anyway.
17 foo.unwrap_or(String::new());
22 foo.unwrap_or_else(String::new);
26 foo.unwrap_or_default();