unnecessary_ final
Learn about the unnecessary_final linter rule.
Don't use final for local variables.
Details
#
Use var, not final, when declaring
local variables.
Per
Effective Dart, there are two styles in wide use. This rule enforces the
var style. For the alternative style that prefers
final, enable prefer_final_locals
and prefer_final_in_for_each instead.
For fields, final is always recommended; see the
rule prefer_final_fields.
BAD:
void badMethod() {
final label = 'Final or var?';
for (final char in ['v', 'a', 'r']) {
print(char);
}
}
GOOD:
void goodMethod() {
var label = 'Final or var?';
for (var char in ['v', 'a', 'r']) {
print(char);
}
}
Incompatible rules
#
The unnecessary_final lint is incompatible with
the following rules:
Enable
#
To enable the unnecessary_final rule, add
unnecessary_final under
linter > rules in your
analysis_options.yaml
file:
linter:
rules:
- unnecessary_final
If you're instead using the YAML map syntax to configure
linter rules, add unnecessary_final: true under
linter > rules:
linter:
rules:
unnecessary_final: true
除非另有说明,文档之所提及适用于 Dart 3.12.2 版本报告页面问题.