fix unary Ops methods: -, +, !

[t-kalinowski]

No description provided.

[mjskay]

I found my way to this PR when I discovered that adding a method for ! did not work in a class I was writing.

From my tests, this PR does not fix this issue for !; e.g. I adapted your test for Double to a Logical and it fails:

Logical := new_class(class_logical)

method(`!`, list(Logical, class_missing)) <- function(e1, e2) {
    Logical(!as.logical(e1))
}
## Error: `generic` is a function, but not an S3 generic function: 
## .Primitive("!")

I think the problem is that "!" %in% group_generics()$Ops is FALSE when it should be TRUE, which stems from the fact that ! is in the Ops S3 group generic but not the Arith, Compare, Logic, or Ops S4 group generics.

As a hackish solution, if I add out$Ops <- union(out$Ops, "!") somewhere after line 116 here:

S7/R/generic-spec.R

Lines 107 to 121 in f75e089

	group_generics <- function() {
	# S3 group generics can be defined by combining S4 group generics
	groups <- list(
	Ops = c("Arith", "Compare", "Logic"),
	Math = c("Math", "Math2"),
	Summary = "Summary",
	Complex = "Complex"
	)
	out <- lapply(groups, function(x) unlist(lapply(x, methods::getGroupMembers)))
	if (getRversion() >= "4.3") {
	out$matrixOps <- c("%*%")
	}
	out
	}

the test on ! succeeds, though I imagine there should be a more elegant solution.

[t-kalinowski]

Thanks for the report and workaround!

This PR will likely be finished / rolled-into #365.

One workaround you can use until this is fixed is to define an S3 method the S3 way.

#' @export
`!.mypackage::Logical` <- function(x) { .... }

That workaround should work now, and continue to work once this is fixed in S7.

[mjskay]

Great thanks! That helps, because I was defining !.ClassName in a previous version of S7 and it stopped working in the latest version; I had missed that the package name is now prepended to the class name.