Macro erecto

macro_rules! erecto {
    ($t:ty) => { ... };
    ($t:ty: $($arg:expr),*) => { ... };
}

Constructs the given type using either the Default::default or new(<optional args>) functions. Calling it with erecto!(type) results in the former, while erecto!(type: <optional args>) results in the latter.

Examples

#[derive(Debug, Default, PartialEq)]
struct Thing {
    x: u8,
}

impl Thing {
    fn new(x: u8) -> Self {
        Self { x }
    }
}

assert_eq!(erecto!(u8), 0);
assert_eq!(erecto!(String), String::default());
assert_eq!(erecto!(String:), String::new());
assert_eq!(erecto!(Thing), Thing::default());
assert_eq!(erecto!(Thing: 5), Thing::new(5));