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input-stream-p Generic Function

Summary

A generic function that determines if an object is an input stream.

Package

common-lisp

Signature

input-stream-p stream => result

Arguments
stream
A stream.
Values
result
A generalized boolean.
Description

The generic function input-stream-p implements the standard function. There are methods with stream specialized on fundamental-stream, fundamental-input-stream and fundamental-output-stream that returns t if stream is an input stream. If you want to implement a stream class with no inherent directionality (and thus does not inherit from fundamental-input-stream or fundamental-output-stream) but for which the directionality depends on the instance, then you should add specialized method for input-stream-p.

Examples

There is an example in 24.2.3 Stream directionality.

See also

input-stream-p in the Common Lisp HyperSpec
fundamental-input-stream
output-stream-p


LispWorks® User Guide and Reference Manual - 01 Dec 2021 19:30:30