#lang typed/racket (: plus : Number Number -> Number) (define (plus x y) (+ x y))
(plus 1 2) (plus "x" 3) 2014-07-20 13:53 GMT+02:00 Jens Axel Søgaard <jensa...@soegaard.net>: > #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 -- -- Jens Axel Søgaard ____________________ Racket Users list: http://lists.racket-lang.org/users
