undefined_shown_name

The library '{0}' doesn't export a member with the shown name '{1}'.

The analyzer produces this diagnostic when a show combinator includes a name that isn't defined by the library being imported.

The following code produces this diagnostic because dart:math doesn't define the name String:

import 'dart:math' show min, String;
​
var x = min(0, 1);

If a different name should be shown, then correct the name. Otherwise, remove the name from the list:

import 'dart:math' show min;
​
var x = min(0, 1);