make-transcoder(3scm)

💅 make-transcoder(3scm) — port transcoders, bestie ✨

okay so this is the make-transcoder(3scm) page from the Scheme Programmer's Manual, and it's literally all about port transcoders. no cap, every detail is staying. 🫶

🌸 NAME 🌸

• make-transcoder
• transcoder-codec
• transcoder-eol-style
• transcoder-error-handling-mode

…all serving port transcoders 💖

📚 LIBRARY 📚

R6RS imports, exactly like this:

(import (rnrs))                     ;R6RS
(import (rnrs io ports))            ;R6RS

✨ SYNOPSIS ✨

(make-transcoder codec)
(make-transcoder codec eol-style)
(make-transcoder codec eol-style handling-mode)

(transcoder-codec transcoder)
(transcoder-eol-style transcoder)
(transcoder-error-handling-mode transcoder)

🎀 DESCRIPTION 🎀

Returns a transcoder with the behavior specified by the arguments. main character energy, honestly.

• codec — must be a codec. The standard codecs are those returned by latin-1-codec, utf-8-codec, and utf-16-codec.
• eol-style — optional, and must be an eol-style(3scm) symbol: lf, cr, crlf, nel, crnel, or ls. It defaults to the native end-of-line style of the underlying platform.
• handling-mode — optional, and must be an error-handling-mode(3scm) symbol: ignore, raise, or replace (default).

🛠️ IMPLEMENTATION NOTES 🛠️

• IronScheme — the native end-of-line style is crlf.

🎁 RETURN VALUES 🎁

Returns a single value which is a transcoder object. one value, one transcoder, slay ✨

💻 EXAMPLES 💻

this example is lowkey iconic:

       ; Decodes a UTF-8-encoded string with ISO-8859-1.
       ; Note also how \r\n is read as a single newline.
       (let* ((bv (string->utf8 "Döner\r\nkebab"))
              (p (open-bytevector-input-port bv))
              (tc (make-transcoder (latin-1-codec)
                                   (eol-style lf)))
              (tp (transcoded-port p tc)))
         (get-string-all tp))
               => "Döner\nkebab"

🌈 APPLICATION USAGE 🌈

This procedure is used in applications that need to control the binary encoding of textual ports.

🧠 RATIONALE 🧠

Transcoders let applications control parameters that would otherwise be implicit. giving you the aux cord, basically 🎧

🦋 COMPATIBILITY 🦋

Transcoders are unique to the R6RS I/O system.

💀 ERRORS 💀

This procedure can raise exceptions with the following condition types:

• &assertion (R6RS) — the wrong number of arguments was passed or an argument was outside its domain.

👀 SEE ALSO 👀

• transcoded-port(3scm)
• port-transcoder(3scm)
• native-transcoder(3scm)
• native-eol-style(3scm)

⭐ STANDARDS ⭐

R6RS

🕰️ HISTORY 🕰️

Port transcoders were introduced in R6RS.

👑 AUTHORS 👑

This page is part of the scheme-manpages project. It includes materials from the RnRS documents. More information can be found at https://github.com/schemedoc/manpages/.

🙈 BUGS 🙈

There is no transcoder? procedure in R6RS. not me looking for it either 😭

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that's a wrap on the make-transcoder(3scm) page from the Scheme Programmer's Manual, dated 2022-03-30 💖 mwah, byeee 🫶✨