multiple_combinators

At most one 'show' or 'hide' combinator can be used on an import or export directive.

Using multiple 'hide' or 'show' combinators is never necessary and often produces surprising results.

The analyzer produces this diagnostic when an import or export directive contains more than one combinator.

The following code produces this diagnostic because the second show combinator hides List and int:

import 'dart:core' show Future, List, int show Future;
​
var x = Future.value(1);

The following code produces this diagnostic because the second hide combinator is redundant:

import 'dart:math' hide Random, max, min hide min;
​
var x = pi;

The following codes produce this diagnostic because the hide combinator is redundant:

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

The following code produces this diagnostic because the show combinator already hides Random and max, so the hide combinator is redundant:

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

If you prefer to list the names that should be visible, then use a single show combinator:

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

If you prefer to list the names that should be hidden, then use a single hide combinator:

import 'dart:math' hide Random, max, min;
​
var x = pi;