description

# Map<K, V>.from constructor

Map<K, V>.from(

1. Map other

)

Creates a LinkedHashMap with the same keys and values as `other`.

The keys must all be instances of `K` and the values of `V`. The `other` map itself can have any type, unlike for Map.of, and the key and value types are checked (and can fail) at run-time.

Prefer using Map.of when possible, and only use `Map.from` to create a new map with more precise types than the original, and when it's known that all the keys and values have those more precise types.

A `LinkedHashMap` requires the keys to implement compatible `operator==` and `hashCode`. It iterates in key insertion order.

    final planets = <num, String>{1: 'Mercury', 2: 'Venus', 3: 'Earth', 4: 'Mars'};
    final mapFrom = Map<int, String>.from(planets);
    print(mapFrom); // {1: Mercury, 2: Venus, 3: Earth, 4: Mars}

## Implementation

    factory Map.from(Map other) = LinkedHashMap<K, V>.from;