operator [] method
The value for the given key
, or null
if key
is not in the map.
Some maps allow null
as a value.
For those maps, a lookup using this operator cannot distinguish between a
key not being in the map, and the key being there with a null
value.
Methods like containsKey or putIfAbsent can be used if the distinction
is important.
Implementation
CandidType? operator [](dynamic key) { // String or int
late int k;
if (key is String) {
k = candid_text_hash(key);
} else
if (key is int) {
k = key;
} else {
throw Exception('must pass in either a String or an int to a fieldtype lookup');
}
return _map[k];
}