I'm fairly sure that this issue exists in other identifiers/commands as well, though I cannot recall any from the top of my head.
Yeah, there are others missing error messages when used incorrectly or with errors that don't help track down the problem. One example is $base() if you use incorrect base types. It doesn't give you an error message other than whatever error may result in it being $null (such as when used as the only item in an echo). For example, $base(1000,50,10). For that matter, it does accept certain base types that aren't really valid (such as 19), though I suppose that just allows for potential new base types. It also does allow for an alphanumeric base conversion, which can be useful even if it doesn't allow for case sensitivity while doing so. So I guess allowing unusual base types if okay... it's just that the ones that aren't allowed don't throw any errors.
There are a variety of others as well that could use improved error reporting.
