stream-element-type (Function)

Syntax:

Arguments and Values:

stream—a stream.

typespec—a type specifier.

Description:

stream-element-type returns a type specifier that indicates the types of objects that may be read from or written to stream.

Streams created by open have an element type restricted to integer or a subtype of type character.

Examples:

;; Note that the stream must accomodate at least the specified type,
;; but might accomodate other types.  Further note that even if it does
;; accomodate exactly the specified type, the type might be specified in
;; any of several ways.
 (with-open-file (s "test" :element-type '(integer 0 1)
                           :if-exists :error
                           :direction :output)
   (stream-element-type s))
→ INTEGER
or→ (UNSIGNED-BYTE 16)
or→ (UNSIGNED-BYTE 8)
or→ BIT
or→ (UNSIGNED-BYTE 1)
or→ (INTEGER 0 1)
or→ (INTEGER 0 (2))

Exceptional Situations:

Should signal an error of type type-error if stream is not a stream.