fromEntries
Builds a Map from an iterable of (key, value) records.
Map<K, V> fromEntries<K, V>(Iterable<(K, V)> entries)
Lecture
This section ports FxTS's object utilities, and the first thing to
understand is the mapping: TypeScript's plain objects become Dart
Maps throughout, and TS's [key, value] entry
tuples become Dart (K, V) records. fromEntries
is the constructor side of that: give it any iterable of records and it
folds them into a Map, last-write-wins on duplicate keys —
exactly like building the map by hand with a loop.
It's the natural partner of entries
(which does the reverse: Map → records) and pairs nicely
with zip, which turns two parallel
lists into exactly the record shape fromEntries wants.
Demo 1 · Basics
Demo 2 · Duplicate keys, and round-tripping with entries
Try it yourself
Exercise: use fromEntries to turn pairs into a Map.