▼ |  | Unstable: May Change Without Warning

1 | Guidelines for Developing unstable Libraries
2 | Automata: Compiling State Machines
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7 | Debugging
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15 | Interface-Oriented Programming for Classes
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26 | Syntax
27 | Temporal Contracts: Explicit Contract Monitors
28 | GUI Libraries

► | 13 | Functions

13.1 | Higher Order Predicates

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13.1`` Higher Order Predicates
conjoin
disjoin

Version: 5.3
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### 13`` Functions

Carl Eastlund <cce@racket-lang.org>

This library is unstable; compatibility will not be maintained. See Unstable: May Change Without Warning for more information.

(require unstable/function)

This module provides tools for higher-order programming and creating functions.

#### 13.1`` Higher Order Predicates

> procedure ((conjoin f ...) x ...) → boolean?
> f : (-> A ... boolean?)
> x : A

Combines calls to each function with and. Equivalent to (and (f x ...) ...)

Examples:
> (define f (conjoin exact? integer?))
> > (f 1)
> #t
> > (f 1.0)
> #f
> > (f 1/2)
> #f
> > (f 0.5)
> #f

> procedure ((disjoin f ...) x ...) → boolean?
> f : (-> A ... boolean?)
> x : A

Combines calls to each function with or. Equivalent to (or (f x ...) ...)

Examples:
> (define f (disjoin exact? integer?))
> > (f 1)
> #t
> > (f 1.0)
> #t
> > (f 1/2)
> #t
> > (f 0.5)
> #f

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