9.1 Multiple Values

See Multiple Return Values for general information about multiple result values. In addition to call-with-values (described in this section), the let-values, let*-values, letrec-values, and define-values forms (among others) create continuations that receive multiple values.

(values v ...) → any

v : any/c

Returns the given vs. That is, values returns as provided arguments.

Examples:
> (values 1)
1
> (values 1 2 3)
1
2
3
> (values)

(call-with-values generator receiver) → any

generator : (-> any)

receiver : procedure?

Calls generator, and passes the values that generator produces as arguments to receiver. Thus, call-with-values creates a continuation that accepts any number of values that receiver can accept. The receiver procedure is called in tail position with respect to the call-with-values call.

Examples:
> (call-with-values (lambda () (values 1 2)) +)
3
> (call-with-values (lambda () 1) (lambda (x y) (+ x y)))
#<procedure>: expects 2 arguments, given 1: 1

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4	Structures
5	Classes and Objects
6	Units
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8	Pattern Matching
9	Control Flow
10	Concurrency and Parallelism
11	Macros
12	Input and Output
13	Reflection and Security
14	Operating System
15	Memory Management
16	Unsafe Operations
17	Running Racket
	Bibliography
	Index

9.1	Multiple Values
9.2	Exceptions
9.3	Delayed Evaluation
9.4	Continuations
9.5	Continuation Marks
9.6	Breaks
9.7	Exiting