Cannot implement unary Ops methods

[teunbrand]

The following attempt at making a unary method for - fails:

library(S7)

foo <- new_class("foo")
method(`-`, list(foo, class_missing)) <- function(e1, e2) {"Minus foo"}

-foo()
#> Error in Ops.S7_object(foo()): argument "e2" is missing, with no default

^{Created on 2025-03-28 with reprex v2.1.1}

I think the cause is that the following lines don't consider the possibility of missing e1 or e2.

S7/R/method-ops.R

Lines 19 to 22 in db59642

	cnd <- tryCatch(
	return(base_ops[[.Generic]](e1, e2)),
	S7_error_method_not_found = function(cnd) cnd
	)

[teunbrand]

Just now noticing #490, so I'll close this