Determine if a function is an S3 generic or S3 method.

is_s3_generic() compares name checks for both internal and regular generics. is_s3_method() builds names of all possible generics for that function and then checks if any of them actually is a generic.

is_s3_generic(fname, env = parent.frame())

is_s3_method(fname, env = parent.frame())

Arguments

fname	Name of function as a string. Need name of function because it's impossible to determine whether or not a function is a S3 method based only on its contents.
env	Environment to search in.

Examples

is_s3_generic("mean")
#> [1] TRUE
is_s3_generic("sum")
#> [1] TRUE
is_s3_generic("[[")
#> [1] TRUE
is_s3_generic("unlist")
#> [1] TRUE
is_s3_generic("runif")
#> [1] FALSE

is_s3_method("t.data.frame")
#> [1] TRUE
is_s3_method("t.test") # Just tricking!
#> [1] FALSE
is_s3_method("as.data.frame")
#> [1] FALSE
is_s3_method("mean.Date")
#> [1] TRUE