Building a new collection out of an existing one is too imperative

[munificent]

Dart has a nice declarative syntax for creating new lists and maps (and eventually probably sets) from a series of elements:

var list = [1, 2, 3];
var map {key: value};

This works well when building a collection out of individual elements. But if you want to insert the contents of an existing collection, you are forced to use an imperative, mutating API:

var args = testArgs.toList()
  ..add('--packages=${PackageMap.globalPackagesPath}')
  ..add('-rexpanded')
  ..addAll(filePaths);

[kevmoo]

@munificent – could this issue be considered closed by the spread collection work?

[munificent]

Yes! This issue is the problem the feature was designed to solve.