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end-of-file

end-of-file Condition Type

Class Precedence List:

end-of-file, stream-error, error, serious-condition, condition, t

Description:

The type end-of-file consists of error conditions related to read operations that are done on streams that have no more data.

See Also:

stream-error-stream

Expanded Reference: end-of-file​

Overview​

end-of-file is a condition type signaled when a read operation is performed on a stream that has no more data. It is a subtype of stream-error.

Catching end-of-file​

(handler-case
    (read-char (make-string-input-stream ""))
  (end-of-file () :got-eof))
=> :GOT-EOF

Accessing the Stream from the Condition​

Since end-of-file inherits from stream-error, you can use stream-error-stream to get the offending stream.

(handler-case
    (read (make-string-input-stream ""))
  (end-of-file (c)
    (streamp (stream-error-stream c))))
=> T

Avoiding end-of-file with eof-error-p​

Most read functions accept an eof-error-p argument. When false, the function returns an eof-value instead of signaling the condition.

(read-char (make-string-input-stream "") nil :eof)
=> :EOF

Type Hierarchy​

(subtypep 'end-of-file 'stream-error)
=> T
=> T

(subtypep 'end-of-file 'error)
=> T
=> T