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This section describes the Lisp functions and variables that pertain
In the functions below, STREAM stands for an input stream (see the
previous section). If STREAM is `nil' or omitted, it defaults to the
value of `standard-input'.
An `end-of-file' error results if an unterminated list or vector is
- Function: read &optional STREAM
This function reads one textual Lisp expression from STREAM,
returning it as a Lisp object. This is the basic Lisp input
- Function: read-from-string STRING &optional START END
This function reads the first textual Lisp expression from the
text in STRING. It returns a cons cell whose CAR is that
expression, and whose CDR is an integer giving the position of the
next remaining character in the string (i.e., the first one not
If START is supplied, then reading begins at index START in the
string (where the first character is at index 0). If END is also
supplied, then reading stops at that index as if the rest of the
string were not there.
(read-from-string "(setq x 55) (setq y 5)")
=> ((setq x 55) . 11)
(read-from-string "\"A short string\"")
=> ("A short string" . 16)
;; Read starting at the first character.
(read-from-string "(list 112)" 0)
=> ((list 112) . 10)
;; Read starting at the second character.
(read-from-string "(list 112)" 1)
=> (list . 6)
;; Read starting at the seventh character,
;; and stopping at the ninth.
(read-from-string "(list 112)" 6 8)
=> (11 . 8)
- Variable: standard-input
This variable holds the default input stream: the stream that
`read' uses when the STREAM argument is `nil'.
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