no_ wildcard_ variable_ uses
Don't use wildcard parameters or variables.
Details
#DON'T use wildcard parameters or variables.
Wildcard parameters and local variables
(e.g. underscore-only names like
_
,
__
,
___
, etc.) will
become non-binding in a future version of the Dart language.
Any existing code that uses wildcard parameters or variables will
break. In anticipation of this change, and to make adoption easier,
this lint disallows wildcard and variable parameter uses.
BAD:
var _ = 1;
print(_); // LINT
void f(int __) {
print(__); // LINT multiple underscores too
}
GOOD:
for (var _ in [1, 2, 3]) count++;
var [a, _, b, _] = [1, 2, 3, 4];
Enable
#
To enable the
no_wildcard_variable_uses
rule, add
no_wildcard_variable_uses
under
linter > rules
in your
analysis_options.yaml
file:
linter:
rules:
- no_wildcard_variable_uses
If you're instead using the YAML map syntax to configure linter rules,
add
no_wildcard_variable_uses: true
under
linter > rules:
linter:
rules:
no_wildcard_variable_uses: true
Unless stated otherwise, the documentation on this site reflects Dart 3.9.2. Report an issue.