Function try_parse_map_entry_constr_loc 

fn try_parse_map_entry_constr_loc<T: Atomic + 'static>(
    pair: Pair<'_, Rule>,
    proc_ident: &String,
) -> Result<T, Error>

Parses a map_boolean_expr into a [Location]

Example: ProcessesLocations\[p\] = "loc1"