Re: [bug #67109] #\return ignored when reading from (current-input-port)

[Retropikzel]

Sorry about this, it seems to be just my own lack of knowledge of the 
R6RS and R7RS. The way the behaviour differed on some implementations 
made it seem like a bug to me. This issue can be closed.

On 09.05.2025 13:17, anonymous wrote:
> URL:
>   <https://savannah.gnu.org/bugs/?67109>
>
>                  Summary: #\return ignored when reading from
> (current-input-port)
>                    Group: MIT/GNU Scheme
>                Submitter: None
>                Submitted: Fri 09 May 2025 10:17:44 AM UTC
>                 Category: None
>                 Severity: 3 - Normal
>                 Priority: 5 - Normal
>               Item Group: Incorrect behavior
>                   Status: None
>                  Privacy: Public
>              Assigned to: None
>          Originator Name: Retropikzel
>         Originator Email: retropikzel@iki.fi
>              Open/Closed: Open
>          Discussion Lock: Any
>                 Keywords:
>
>
>     _______________________________________________________
>
> Follow-up Comments:
>
>
> -------------------------------------------------------
> Date: Fri 09 May 2025 10:17:44 AM UTC By: Anonymous
> I’m making a portable CGI library and reading characters from the
> (current-input-port), I noticed that MIT-scheme leaves out #\return 
> characters
> when reading from (current-input-port). I’ve made a some tests to 
> showcase
> the bug.
>
> read-char.scm:
> (import (scheme base)
>         (scheme read)
>         (scheme write))
>
> (letrec* ((looper (lambda ()
>                     (let ((c (read-char (current-input-port))))
>                       (when (not (eof-object? c))
>                         (write c)
>                         (newline)
>                         (looper))))))
>   (looper))
>
>
> Run with: printf "Hello\r\n" | <IMPLEMENTATION COMMAND> read-char.scm
>
> Output on Chibi, Chicken, Cyclone, Gambit(interpreter), Foment, Gauche, 
> Guile,
> Kawa, Larceny, Racket, Skint, Stklos, tr7:
>
> #\H
> #\e
> #\l
> #\l
> #\o
> #\return
> #\newline
>
> Output on mit-scheme, Sagittarius:
> #\H
> #\e
> #\l
> #\l
> #\o
> #\newline
>
> Output on Loko, Mosh, ypsilon:
> #\H
> #\e
> #\l
> #\l
> #\o
> #\linefeed
>
>
> read-string.scm:
> (import (scheme base)
>         (scheme read)
>         (scheme write))
>
> (define text-port (open-input-string (string-append "Hello"
>                                                     (string #\return)
>                                                     (string 
> #\newline))))
> (letrec* ((looper (lambda ()
>                     (let ((c (read-char text-port)))
>                       (when (not (eof-object? c))
>                         (write c)
>                         (newline)
>                         (looper))))))
>   (looper))
>
> Run with: <IMPLEMENTATION COMMAND> read-string.scm
>
> Output on Chibi, Chicken, Cyclone, Gambit(interpreter) Foment, Gauche, 
> Guile,
> Kawa, Larceny, mit-scheme, Racket, Sagittarius, skint, STklos, tr7:
> #\H
> #\e
> #\l
> #\l
> #\o
> #\return
> #\newline
>
> Output on Loko, Mosh, ypsilon:
> #\H
> #\e
> #\l
> #\l
> #\o
> #\return
> #\linefeed
>
>
>
>
>
>
>
>     _______________________________________________________
>
> Reply to this item at:
>
>   <https://savannah.gnu.org/bugs/?67109>
>
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