Is something like this possible?
(define (create-greeter greeting)
(lambda (n)
(println greeting " " n "!")))
(set 'hello-greeter (create-greeter "Hello"))
(set 'goodbye-greeter (create-greeter "Goodbye"))
(hello-greeter "World")
(goodbye-greeter "World")
The obvious desired output is:
Hello World
Goodbye World
Jeremy
Hi Jeremy,
Something like this, maybe:
> (define (greeter greeting to) (println greeting " " to "!"))
(lambda (greeting to) (println greeting " " to "!"))
> (set 'hello (curry greeter "Hello"))
(lambda (_x) (greeter "Hello" _x))
> (set 'goodbye (curry greeter "Goodbye"))
(lambda (_x) (greeter "Goodbye" _x))
> (hello "World")
Hello World!
"!"
> (goodbye "Cruel World")
Goodbye Cruel World!
"!"
> _
m i c h a e l
'curry' is the shortest and preferred way to do it when you have 2 arguments as in Jeremyc's example. The following is a more general solution in case there are more parameters or it is not the 1st one which gets
This uses expand to get the curried variable into the lambda expression:
(expand (fn (n) (println greeting " " n "!")) 'greeting))
> (create-greeter "Hello")
(lambda (n) (println "Hello" " " n "!"))
> (define hello-greeter (create-greeter "Hello"))
(lambda (n) (println "Hello" " " n "!"))
> (hello-greater "World")
Hello World!
instead of (define hello-greeter ...) you also could say (set 'hello-greeter ..) as in your code. Both does the same in newLISP, but 'define' is just a little bit more descriptive in this case.
Lutz