Rule idea: no-duplicate-at-functions: Disallow duplicate functions within a stylesheet

[Grawl]

There are two rules to disallow duplicates dollar variables and mixins:

no-duplicate-dollar-variables: Disallow duplicate dollar variables within a stylesheet.

no-duplicate-mixins: Disallow duplicate mixins within a stylesheet.

But there is no rule to disallow duplicate SCSS @-functions.

In my idea, following code patterns are considered warnings:

@function foo($arg) {
    @return $arg * 2;
}
@function foo($arg) {
    @return $arg * 4;
}

[kristerkari]

Thanks! I think that it indeed would make sense to have such rule.