Macro maybe_par

macro_rules! maybe_par {
    ($prefix:ident.$name:ident.iter().$operator:ident($($rest:expr)*), $threshold:expr) => { ... };
    ($prefix:ident.$name:ident.into_iter().$operator:ident($($rest:expr)*), $threshold:expr) => { ... };
    ($name:ident.iter().$operator:ident($($rest:expr)*), $threshold:expr) => { ... };
    ($name:ident.into_iter().$operator:ident($($rest:expr)*), $threshold:expr) => { ... };
    ($name:ident.iter_mut().$operator:ident($($rest:expr)*), $threshold:expr) => { ... };
    ($name:ident.iter().$operator:ident($($rest:expr)*).$operator2:ident($($rest2:expr)*), $threshold:expr) => { ... };
    ($name:ident.into_iter().$operator:ident($($rest:expr)*).$operator2:ident($($rest2:expr)*), $threshold:expr) => { ... };
    ($name:ident.iter_mut().$operator:ident($($rest:expr)*).$operator2:ident($($rest2:expr)*), $threshold:expr) => { ... };
    ($name:ident.iter().$operator:ident($($rest:expr)*).$operator2:ident::<$t:ty>($($rest2:expr)*), $threshold:expr) => { ... };
    ($name:ident.iter().$operator:ident($($rest:expr)*).$operator2:ident($($rest2:expr)*).$operator3:ident($($rest3:expr)*), $threshold:expr) => { ... };
}