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+#+TITLE: Where next for guile-prescheme?
+
+* TODO guile repl integration
+
+Currently the "prescheme" language definition is just scheme with a different
+default environment (aka. the "prelude", the stuff that's imported by default).
+
+In the Guile REPL you can =,L prescheme= to switch language, but it's not very
+useful because you stay in the guile-user module, which is Guile's default
+environment, not Pre-Scheme's!
+
+You can create a Pre-Scheme module and switch into it with some effort:
+
+#+BEGIN_SRC scheme
+(use-modules (system base language))
+(set-module-name! (default-environment 'prescheme) '(prescheme-user))
+,module prescheme-user
+,language prescheme
+#+END_SRC
+
+We need to make the process of "give me a Pre-Scheme REPL" easier.  Maybe just
+ship a REPL launcher script which starts up in Pre-Scheme instead of Guile?
+
+* TODO translate s48 macros to syntax-case
+
+Scheme 48 uses "explicit renaming" macros, these should be ported to
+syntax-case.
+
+#+BEGIN_SRC scheme
+;; scheme48-1.9.2/scheme/alt/define-macro-define-syntax.scm
+(define-macro (define-syntax macro-name transformer . stuff)
+  `(define-macro (,macro-name . args)
+     (,transformer (cons ',macro-name args)
+                   (lambda (x) x)
+                   eq?)))
+#+END_SRC
+
+** TODO prescheme/s48-defenum.scm
+- define-enumeration
+** TODO prescheme/ps-defenum.scm
+- define-external-enumeration
+** TODO prescheme/prescheme.scm
+- goto
+- external
+
+* TODO prepare some compatibility tests
+
+We need to find collect all the "real-world" Pre-Scheme we can get our hands on,
+and test that our Guile Pre-Scheme produces identical output to Scheme 48
+Pre-Scheme.
+
+Exhibit A is the "hello world" from the manual:
+
+#+BEGIN_SRC scheme
+;; https://thintz.com/resources/prescheme-documentation#Example-Pre_002dScheme-compiler-usage
+(define (main argc argv)
+  (if (= argc 2)
+      (let ((out (current-output-port)))
+        (write-string "Hello, world, " out)
+        (write-string (vector-ref argv 1) out)
+        (write-char #\! out)
+        (newline out)
+        0)
+      (let ((out (current-error-port)))
+        (write-string "Usage: " out)
+        (write-string (vector-ref argv 0) out)
+        (write-string " <user>" out)
+        (newline out)
+        (write-string "  Greets the world & <user>." out)
+        (newline out)
+        -1)))
+#+END_SRC
+
+* TODO write more TODOs