.list me
        .macro test x
        .blkb x               ; test some directive that wants an expression
        .endm

        size = 10
        foo = 2

    ; likes:

        test size             ; not replaced by "10"
        test \size            ; replaced by "10"
        test \<size>          ; ditto
        test \<size + foo>    ; replaced by "12"
        test ^/size + foo/    ; arg is "size + foo", not "12"

    ; dislikes:

        test <\size>          ; parameter is \size, which might be ok for
                              ; macros where the argument is used differently.
        test size + foo       ; gets split at the space
        test /size + foo/     ; gets split at the space
        test \/size + foo/    ; invalid expression with division operator
        test \^/size + foo/   ; original dislikes this, but we accept it.