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authorNeil Jerram <neil@ossau.uklinux.net>2001-03-10 14:07:19 +0000
committerNeil Jerram <neil@ossau.uklinux.net>2001-03-10 14:07:19 +0000
commit451d273ac98c0b7f0e5e2c9e267ff14170babf23 (patch)
treefb9b9a4c6d83dc83bcd3399fbdc85ee55f54ad28
parent97d0e20b2e19ac8e8b7310ce2a72a69f02ee6a60 (diff)
downloadguile-451d273ac98c0b7f0e5e2c9e267ff14170babf23.tar.gz
Make (ice-9 buffered-input) more general
-rw-r--r--ice-9/ChangeLog9
-rw-r--r--ice-9/buffered-input.scm52
2 files changed, 44 insertions, 17 deletions
diff --git a/ice-9/ChangeLog b/ice-9/ChangeLog
index d414850dc..0d43f134d 100644
--- a/ice-9/ChangeLog
+++ b/ice-9/ChangeLog
@@ -1,3 +1,12 @@
+2001-03-10 Neil Jerram <neil@ossau.uklinux.net>
+
+ * buffered-input.scm (make-buffered-input-port): New, more general
+ buffered input procedure. Does not assume that a newline
+ character should be interpolated between chunks of input returned
+ by the reader proc.
+ (make-line-buffered-input-port): Redefine in terms of
+ make-buffered-input-port.
+
2001-03-09 Keisuke Nishida <kxn30@po.cwru.edu>
* match.scm: Don't export defstruct. Use (unquote defstruct) instead.
diff --git a/ice-9/buffered-input.scm b/ice-9/buffered-input.scm
index df42cd533..c289a58a3 100644
--- a/ice-9/buffered-input.scm
+++ b/ice-9/buffered-input.scm
@@ -18,7 +18,8 @@
;;;; Boston, MA 02111-1307 USA
(define-module (ice-9 buffered-input)
- #:export (make-line-buffered-input-port
+ #:export (make-buffered-input-port
+ make-line-buffered-input-port
set-buffered-input-continuation?!))
;; @code{buffered-input-continuation?} is a property of the ports
@@ -29,20 +30,18 @@
(define (set-buffered-input-continuation?! port val)
"Set the read continuation flag for @var{port} to @var{val}.
-See @code{make-line-buffered-input-port} for the meaning and use of
-this flag."
+See @code{make-buffered-input-port} for the meaning and use of this
+flag."
(set! (buffered-input-continuation? port) val))
-(define (make-line-buffered-input-port reader)
+(define (make-buffered-input-port reader)
"Construct a line-buffered input port from the specified @var{reader}.
@var{reader} should be a procedure of one argument that somehow reads
-a line of input and returns it as a string @emph{without} the
-terminating newline character.
+a chunk of input and returns it as a string.
-The port created by @code{make-line-buffered-input-port} automatically
-adds a newline character after each string returned by @var{reader};
-this makes these ports useful for reading strings that extend across
-more than one input line.
+The port created by @code{make-buffered-input-port} does @emph{not}
+interpolate any additional characters between the strings returned by
+@var{reader}.
@var{reader} should take a boolean @var{continuation?} argument.
@var{continuation?} indicates whether @var{reader} is being called to
@@ -54,12 +53,12 @@ use the @var{continuation?} argument to determine what prompt to
display to the user.
The new/continuation distinction is largely an application-level
-concept, and @code{set-buffered-input-continuation?!} allows an
-application some control over when a read operation is considered to
-be new. But note that if there is data already buffered in the port
-when a new read operation starts, this data will be read before the
-first call to @var{reader}, and so @var{reader} will be called with
-@var{continuation?} set to @code{#t}."
+concept: @code{set-buffered-input-continuation?!} allows an
+application to specify when a read operation is considered to be new.
+But note that if there is non-whitespace data already buffered in the
+port when a new read operation starts, this data will be read before
+the first call to @var{reader}, and so @var{reader} will be called
+with @var{continuation?} set to @code{#t}."
(let ((read-string "")
(string-index -1))
(letrec ((get-character
@@ -69,7 +68,7 @@ first call to @var{reader}, and so @var{reader} will be called with
read-string)
((>= string-index (string-length read-string))
(set! string-index -1)
- #\nl)
+ (get-character))
((= string-index -1)
(set! read-string (reader (buffered-input-continuation? port)))
(set! string-index 0)
@@ -87,4 +86,23 @@ first call to @var{reader}, and so @var{reader} will be called with
(set! (buffered-input-continuation? port) #f)
port)))
+(define (make-line-buffered-input-port reader)
+ "Construct a line-buffered input port from the specified @var{reader}.
+@var{reader} should be a procedure of one argument that somehow reads
+a line of input and returns it as a string @emph{without} the
+terminating newline character.
+
+The port created by @code{make-line-buffered-input-port} automatically
+interpolates a newline character after each string returned by
+@var{reader}.
+
+@var{reader} should take a boolean @var{continuation?} argument. For
+the meaning and use of this argument, see
+@code{make-buffered-input-port}."
+ (make-buffered-input-port (lambda (continuation?)
+ (let ((str (reader continuation?)))
+ (if (eof-object? str)
+ str
+ (string-append str "\n"))))))
+
;;; buffered-input.scm ends here