Std.EnumMap.mergeWith
1 declaration
fn
mergeWith: &Std.EnumMap.EnumMap[K, V] -> &Std.EnumMap.EnumMap[K, V] -> fn(V, V) -> V -> Std.EnumMap.EnumMap[K, V]This is a callable function.
What it does
Two maps over the same domain combined value by value.
The domain is the first map's. A key the second map lacks keeps the first
map's value untouched, so combining a full week with a partial one leaves
the untouched days alone rather than reporting a domain mismatch the caller
would have to handle on every call.
Read the signature
- The text after the name is the type checked by Pudu.
- Read arrows from left to right: inputs come first, and the final type is returned.
- & borrows a value for this call instead of moving or copying it.
- Names inside [ ] are type arguments, such as the item type held by a collection.