(display <char>) is not equiv. of put-char

[GoogleCodeExporter]

What steps will reproduce the problem?
1. (display #\tab)

What is the expected output? What do you see instead?
this should print TAB character(9). but "x9;"

There is no standard semantics for DISPLAY procedure(AFAIK)
but (display <char> PORT) should be same as (put-char PORT <char>)
like Chez Scheme.

Original issue reported on code.google.com by oku...@gmail.com on 9 Jan 2011 at 1:16

[GoogleCodeExporter]

cc higepon.

Original comment by oku...@gmail.com on 9 Jan 2011 at 1:36

• Added labels: Type-Enhancement
• Removed labels: Type-Other

[GoogleCodeExporter]

Fixed.
https://github.com/higepon/mosh/commit/301fec9454bb46b78b2d2ffc13de609e7444aa65

Original comment by hige...@gmail.com on 9 Jan 2011 at 1:54

• Changed state: Fixed

[GoogleCodeExporter]

There is still something wrong:

$ mosh-script proof.sps
"x10FFFF; x1;"
$ cat proof.sps
#!r6rs
(import (rnrs))

(let-values (((port getter) (open-string-output-port)))
  (display #\x0010FFFF port)
  (display " " port)
  (display #\x000000001 port)
  (write (getter)))
(newline)

Original comment by mrc....@gmail.com on 5 Feb 2011 at 9:23

[GoogleCodeExporter]

reopened.

DISPLAY might escape unprintable chars(except whitespaces and returns).
Because their displaying representation is not specified in R6RS...

If you really want to do this (in R6RS portable way), use put-char or 
put-string instead.

prism:check oku$ nmosh check.sps 
"\x10FFFF; \x1;"
prism:check oku$ cat check.sps 
#!r6rs
(import (rnrs))

(let-values (((port getter) (open-string-output-port)))
  (put-char port #\x0010FFFF)
  (put-string port " ")
  (put-char port #\x000000001)
  (write (getter)))
(newline)

IMO, these should be handled with transcoders and (display <char>) should be 
equivalent with put-char
as subject of this bug says.

Original comment by oku...@gmail.com on 5 Feb 2011 at 10:19

• Changed state: Accepted

[GoogleCodeExporter]

I confirmed the problem using this:

#!r6rs
(import (rnrs) 
        (srfi :8) (srfi :42))

(define (check id)
  (let ((c (integer->char id)))
    (define (using-display port return)
      (display c port)
      (return))
    (define (using-put-char port return)
      (put-char port c)
      (return))
    (let ((dsp (call-with-values open-string-output-port using-display))
          (pcr (call-with-values open-string-output-port using-put-char)))
      (unless (string=? dsp pcr)
        (write (list 'ID: id dsp pcr)) (newline)))))

(do-ec (: i 0 #xd800)
       (check i))

(do-ec (: i #xe000 #x110000)
       (check i))

Original comment by oku...@gmail.com on 5 Feb 2011 at 10:37

[GoogleCodeExporter]

Original comment by hige...@gmail.com on 26 Apr 2011 at 1:57

• Added labels: Milestone-Release0.3.0