Generic Function

Summary

A function used by listen that returns t if there is input available.

Package

stream

Signature

stream-listen stream => bool

Arguments

stream

A stream.

Values

bool

A generalized boolean.

Description

The generic function stream-listen is used by listen and returns t if there is input available. The default method uses stream-read-char-no-hang and stream-unread-char . Most streams should define their own method as this is usually trivial and more efficient than the method provided.

See also

stream-read-char-no-hang
stream-unread-char