#lang racket (define (plus x y) (unless (and (number? x) (number? y)) (error 'plus (~a "expected two numbers, got: " x " " y))) (+ x y))
(plus 1 2) (plus "x" 3) 2014-07-20 13:04 GMT+02:00 קוראל אלימלך <coral2...@gmail.com>: > How can i define that a function will get an integer argument? > > is its possible? > > for example: > (define (func (x::Number))) /// its not working that way > > and if ill call the function with string there will be an error.. > > ____________________ > Racket Users list: > http://lists.racket-lang.org/users > -- -- Jens Axel Søgaard ____________________ Racket Users list: http://lists.racket-lang.org/users