base64: Turn into a regular Guile module.

* guix/base64.scm: Replace 'library' form with 'define-module'.

guix/base64.scm

@@ -5,6 +5,7 @@
 ;; February 12, 2014.
 ;;
 ;; Some optimizations made by Ludovic Courtès <ludo@gnu.org>, 2015.
+;; Turned into a Guile module (instead of R6RS).
 ;;
 ;; This program is free software: you can redistribute it and/or modify
 ;; it under the terms of the GNU General Public License as published by
@@ -42,23 +43,20 @@
 ;;   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 ;;   DEALINGS IN THE SOFTWARE.
 
-#!r6rs
-
 ;; RFC 4648 Base-N Encodings
 
-(library (guix base64)
-  (export base64-encode
+(define-module (guix base64)
+  #:export (base64-encode
             base64-decode
             base64-alphabet
             base64url-alphabet
             get-delimited-base64
             put-delimited-base64)
-  (import (rnrs)
-          (only (srfi :13 strings)
-                string-index
+  #:use-module (rnrs)
+  #:use-module ((srfi srfi-13)
+                #:select (string-index
                           string-prefix? string-suffix?
-                string-concatenate string-trim-both)
-          (only (guile) ash logior))
+                          string-concatenate string-trim-both)))
 
 
 (define-syntax define-alias
@@ -68,6 +66,7 @@
 
 ;; Force the use of Guile's own primitives to avoid the overhead of its 'fx'
 ;; procedures.
+
 (define-alias fxbit-field bitwise-bit-field)
 (define-alias fxarithmetic-shift ash)
 (define-alias fxarithmetic-shift-left ash)
@@ -143,6 +142,7 @@
 
   ;; Decodes a base64 string. The string must contain only pure
   ;; unpadded base64 data.
+  
 (define base64-decode
   (case-lambda
     ((str)
@@ -201,6 +201,7 @@
   ;; the given port. Returns two values: a string with the type and a
   ;; bytevector containing the base64 decoded data. The second value
   ;; is the eof object if there is an eof before the BEGIN delimiter.
+  
 (define (get-delimited-base64 port)
   (define (get-first-data-line port)
     ;; Some MIME data has header fields in the same format as mail
@@ -249,4 +250,4 @@
                     line-length #f base64-alphabet port)
      (display (string-append "\n-----END " type "-----\n") port))
     ((port type bv)
-       (put-delimited-base64 port type bv 76)))))
+     (put-delimited-base64 port type bv 76))))