Description
no_leading_underscores_for_local_identifiers would be a good candidate for recommended if not core.
Lint Description:
DON’T use a leading underscore for identifiers that aren't private. Dart
uses a leading underscore in an identifier to mark members and top-level
declarations as private. This trains users to associate a leading underscore
with one of those kinds of declarations. They see _ and think "private".
There is no concept of "private" for local variables or parameters. When one of
those has a name that starts with an underscore, it sends a confusing signal to
the reader. To avoid that, don't use leading underscores in those names.
Exception: An unused parameter can be named _, __, ___, etc. This is
common practice in callbacks where you are passed a value but you don't need
to use it. Giving it a name that consists solely of underscores is the idiomatic
way to indicate that the value isn't used.
BAD
void print(String _name) {
var _size = _name.length;
...
}GOOD:
void print(String name) {
var size = name.length;
...
}OK:
[1,2,3].map((_) => print('Hello'));We might also consider no_leading_underscores_for_library_prefixes.