Overloading Ampersand & operator in R

Question

I like to overload my ampersand operator with paste. So that way I can paste stuff easily. Like this:

R> \"Hello\" & \" World\"
 [1] \"Hello World\"


        

Answer 1

I think defining &.default to use paste is just wrong:

`&` <- function(e1, e2) UseMethod("&", c(e1, e2))
`&.default` <- function(e1, e2) .Primitive("&")(e1, e2)
`&.character` <- function(e1, e2) paste(e1, e2)
"Hello" & "World"
[1] "Hello World"
 1*0
#[1] 0
 1&0
#[1] FALSE
 1&1
#[1] TRUE

Answer 2

You'll need to use the S3 object system in R:

`&` <- function(e1, e2) UseMethod("&", c(e1, e2))
`&.default` <- function(e1, e2) paste(e1, e2)
`&.logical` <- function(e1, e2) .Primitive("&")(e1, e2)

Now you can use & as you would expect:

> 1 & 2
[1] "1 2"
> TRUE & FALSE
[1] FALSE
> "Hello" & "World"
[1] "Hello World"
>