[nongnu] elpa/geiser-racket ac0f055 002/191: Racket: PLT implementation renamed to Racket.

[Philip Kaludercic]

branch: elpa/geiser-racket
commit ac0f0556bbaf73cd41de19f4971fc02bac18fbdf
Author: Jose Antonio Ortega Ruiz <jao@gnu.org>
Commit: Jose Antonio Ortega Ruiz <jao@gnu.org>

    Racket: PLT implementation renamed to Racket.
---
 geiser.rkt             |  22 ++++++
 geiser/autodoc.rkt     | 189 +++++++++++++++++++++++++++++++++++++++++++++++++
 geiser/completions.rkt |  31 ++++++++
 geiser/enter.rkt       | 103 +++++++++++++++++++++++++++
 geiser/eval.rkt        |  81 +++++++++++++++++++++
 geiser/locations.rkt   |  54 ++++++++++++++
 geiser/main.rkt        |  47 ++++++++++++
 geiser/modules.rkt     | 150 +++++++++++++++++++++++++++++++++++++++
 geiser/user.rkt        |  56 +++++++++++++++
 geiser/utils.rkt       |  27 +++++++
 10 files changed, 760 insertions(+)

diff --git a/geiser.rkt b/geiser.rkt
new file mode 100644
index 0000000..45d1289
--- /dev/null
+++ b/geiser.rkt
@@ -0,0 +1,22 @@
+;;; geiser.rkt -- entry point
+
+;; Copyright (C) 2009, 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Sat Apr 25, 2009 22:36
+
+;;; Code:
+
+(require version/utils)
+(unless (version<=? "5.0" (version))
+  (error 'geiser
+         "Racket version 5.0 or better required (found ~a)"
+         (version)))
+
+(require geiser/user)
+
+;;; geiser.rkt ends here
diff --git a/geiser/autodoc.rkt b/geiser/autodoc.rkt
new file mode 100644
index 0000000..0bb850d
--- /dev/null
+++ b/geiser/autodoc.rkt
@@ -0,0 +1,189 @@
+;;; autodoc.rkt -- suport for autodoc echo
+
+;; Copyright (C) 2009, 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Sun May 03, 2009 14:45
+
+#lang racket
+
+(provide autodoc update-signature-cache get-help)
+
+(require geiser/utils geiser/modules geiser/locations scheme/help)
+
+(define (get-help symbol mod)
+  (with-handlers ((exn? (lambda (_)
+                          (eval `(help ,symbol)))))
+    (eval `(help ,symbol #:from ,(ensure-module-spec mod)))))
+
+(define (autodoc ids)
+  (if (not (list? ids))
+      '()
+      (map (lambda (id) (or (autodoc* id) (list id))) ids)))
+
+(define (autodoc* id)
+  (and
+   (symbol? id)
+   (let* ((loc (symbol-location* id))
+          (name (car loc))
+          (path (cdr loc))
+          (sgns (and path (find-signatures path name id)))
+          (sgns (and sgns (if (list? sgns) sgns '()))))
+     (and sgns
+          `(,id
+            (name . ,name)
+            (args ,@(map format-signature sgns))
+            (module . ,(module-path-name->name path)))))))
+
+(define (format-signature sign)
+  (if (signature? sign)
+      `((required ,@(signature-required sign))
+        (optional ,@(signature-optional sign)
+                  ,@(let ((rest (signature-rest sign)))
+                      (if rest (list "...") '())))
+        (key ,@(signature-keys sign)))
+      '()))
+
+(define signatures (make-hash))
+
+(define-struct signature (required optional keys rest))
+
+(define (find-signatures path name local-name)
+  (let ((path (if (path? path) (path->string path) path)))
+    (hash-ref! (hash-ref! signatures
+                          path
+                          (lambda () (parse-signatures path)))
+               name
+               (lambda () (infer-signatures local-name)))))
+
+(define (parse-signatures path)
+  (let ((result (make-hasheq)))
+    (with-handlers ((exn? (lambda (e) result)))
+      (with-input-from-file path
+        (lambda ()
+          (parameterize ((read-accept-reader #t))
+            (let loop ((stx (read-syntax path)))
+              (cond ((eof-object? stx) void)
+                    ((syntax->datum stx) =>
+                     (lambda (datum)
+                       (parse-datum! datum result)
+                       (loop (read-syntax path))))
+                    (else void)))))))
+    result))
+
+(define (parse-datum! datum store)
+  (with-handlers ((exn? (lambda (_) void)))
+    (match datum
+      (`(module ,name ,lang (#%module-begin . ,forms))
+       (for-each (lambda (f) (parse-datum! f store)) forms))
+      (`(module ,name ,lang . ,forms)
+       (for-each (lambda (f) (parse-datum! f store)) forms))
+      (`(define ((,name . ,formals) . ,_) . ,_)
+       (add-signature! name formals store))
+      (`(define (,name . ,formals) . ,_)
+       (add-signature! name formals store))
+      (`(define ,name (lambda ,formals . ,_))
+       (add-signature! name formals store))
+      (`(define ,name (case-lambda ,clauses ...))
+       (for-each (lambda (c) (add-signature! name (car c) store))
+                 (reverse clauses)))
+      (`(define-for-syntax (,name . ,formals) . ,_)
+       (add-signature! name formals store))
+      (`(define-for-syntax ,name (lambda ,formals . ,_))
+       (add-signature! name formals store))
+      (`(define-syntax-rule (,name . ,formals) . ,_)
+       (add-signature! name formals store))
+      (`(define-syntax ,name (syntax-rules ,specials . ,clauses))
+       (for-each (lambda (c) (add-signature! name (cdar c) store))
+                 (reverse clauses)))
+      (`(define-syntax ,name (lambda ,_ (syntax-case ,_ . ,clauses)))
+       (for-each (lambda (c) (add-signature! name (cdar c) store))
+                 (reverse clauses)))
+      (_ void))))
+
+(define (add-signature! name formals store)
+  (when (symbol? name)
+    (hash-set! store
+               name
+               (cons (parse-formals formals)
+                     (hash-ref store name '())))))
+
+(define (parse-formals formals)
+  (let loop ((formals formals) (req '()) (opt '()) (keys '()))
+    (cond ((null? formals)
+           (make-signature (reverse req) (reverse opt) (reverse keys) #f))
+          ((symbol? formals)
+           (make-signature (reverse req) (reverse opt)
+                           (reverse keys) formals))
+          ((pair? (car formals)) (loop (cdr formals)
+                                       req
+                                       (cons (car formals) opt)
+                                       keys))
+          ((keyword? (car formals)) (let* ((kname
+                                            (keyword->symbol (car formals)))
+                                           (arg-id (cadr formals))
+                                           (name (if (pair? arg-id)
+                                                     (list kname
+                                                           (cadr arg-id))
+                                                     kname)))
+                                      (loop (cddr formals)
+                                            req
+                                            opt
+                                            (cons name keys))))
+          (else (loop (cdr formals) (cons (car formals) req) opt keys)))))
+
+(define (infer-signatures name)
+  (define syntax-tag (cons 1 0))
+  (define error-tag (cons 1 1))
+  (define generic-signature (make-signature '(...) '() '() #f))
+  (let ((value (with-handlers ((exn:fail:syntax? (lambda (_) syntax-tag))
+                               (exn:fail:contract:variable? (lambda (_)
+                                                              error-tag)))
+                 (namespace-variable-value name))))
+    (cond ((procedure? value) (arity->signatures (procedure-arity value)))
+          ((eq? value syntax-tag) (list generic-signature))
+          ((eq? value error-tag) #f)
+          (else 'variable))))
+
+(define (arity->signatures arity)
+  (define (args fst count)
+    (let* ((letts (list->vector '(#\x #\y #\z #\u #\v #\w #\r #\s)))
+           (len (vector-length letts))
+           (lett (lambda (n) (vector-ref letts (modulo n len)))))
+      (map (lambda (n) (string->symbol (format "~a" (lett n))))
+           (build-list count (lambda (n) (+ n fst))))))
+  (define (arity->signature arity)
+    (cond ((number? arity)
+           (make-signature (args 0 arity) '() '() #f))
+          ((arity-at-least? arity)
+           (make-signature (args 0 (arity-at-least-value arity))
+                           '() '() 'rest))))
+  (define (conseq? lst)
+    (cond ((< (length lst) 2) (number? (car lst)))
+          ((and (number? (car lst))
+                (number? (cadr lst))
+                (eqv? (+ 1 (car lst)) (cadr lst)))
+           (conseq? (cdr lst)))
+          (else #f)))
+  (cond ((and (list? arity) (conseq? arity))
+         (let ((mi (apply min arity))
+               (ma (apply max arity)))
+           (list (make-signature (args 0 mi) (args mi (- ma mi)) '() #f))))
+        ((list? arity) (map arity->signature arity))
+        (else (list (arity->signature arity)))))
+
+(define (update-signature-cache path . form)
+  (when (and (string? path)
+             (or (null? form)
+                 (and (list? (car form))
+                      (not (null? (car form)))
+                      (memq (caar form)
+                            '(define-syntax-rule
+                               define-syntax define set! define-struct)))))
+    (hash-remove! signatures path)))
+
+;;; autodoc.rkt ends here
diff --git a/geiser/completions.rkt b/geiser/completions.rkt
new file mode 100644
index 0000000..4cbc09f
--- /dev/null
+++ b/geiser/completions.rkt
@@ -0,0 +1,31 @@
+;;; completions.rkt -- completion support
+
+;; Copyright (C) 2009, 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Sun Apr 26, 2009 19:02
+
+#lang racket
+
+(provide symbol-completions
+         module-completions)
+
+(require srfi/13 geiser/utils geiser/modules)
+
+(define (filter-prefix prefix lst sort?)
+  (filter (lambda (s) (string-prefix? prefix s))
+          (if sort? (sort lst string<?) lst)))
+
+(define (symbol-completions prefix)
+  (filter-prefix prefix
+                 (map symbol->string (namespace-mapped-symbols))
+                 #t))
+
+(define (module-completions prefix)
+  (filter-prefix prefix (module-list) #f))
+
+;;; completions.rkt ends here
diff --git a/geiser/enter.rkt b/geiser/enter.rkt
new file mode 100644
index 0000000..eff37f6
--- /dev/null
+++ b/geiser/enter.rkt
@@ -0,0 +1,103 @@
+;;; enter.rkt -- custom module loaders
+
+;; Copyright (C) 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Wed Mar 31, 2010 21:53
+
+#lang racket/base
+
+(require syntax/modcode
+         (for-syntax scheme/base))
+
+(provide get-namespace enter-module module-loader module-loaded?)
+
+(define-struct mod (name timestamp depends))
+
+(define loaded (make-hash))
+
+(define (module-loaded? path)
+  (with-handlers ((exn? (lambda (_) #f)))
+    (let ((rp (module-path-index-resolve (module-path-index-join path #f))))
+      (hash-has-key? loaded (resolved-module-path-name rp)))))
+
+(define (enter-module mod)
+  (dynamic-require mod #f)
+  (check-latest mod))
+
+(define (module-loader orig)
+  (enter-load/use-compiled orig #f))
+
+(define (notify re? path)
+  (when re?
+    (fprintf (current-error-port) " [re-loading ~a]\n" path)))
+
+(define inhibit-eval (make-parameter #f))
+
+(define (get-namespace mod)
+  (parameterize ([inhibit-eval #t])
+    (module->namespace mod)))
+
+(define ((enter-load/use-compiled orig re?) path name)
+  (when (inhibit-eval)
+    (raise (make-exn:fail "namespace not found"
+                          (current-continuation-marks))))
+  (if name
+      ;; Module load:
+      (let ([code (get-module-code path "compiled" compile
+                                   (lambda (ext loader?)
+                                     (load-extension ext)
+                                     #f)
+                                   #:notify (lambda (chosen)
+                                              (notify re? chosen)))]
+            [path (normal-case-path
+                   (simplify-path
+                    (path->complete-path path
+                                         (or (current-load-relative-directory)
+                                             (current-directory)))))])
+        ;; Record module timestamp and dependencies:
+        (let ([mod (make-mod name
+                             (get-timestamp path)
+                             (if code
+                                 (apply append
+                                        (map cdr (module-compiled-imports 
code)))
+                                 null))])
+          (hash-set! loaded path mod))
+        ;; Evaluate the module:
+        (eval code))
+      ;; Not a module:
+      (begin
+        (notify re? path)
+        (orig path name))))
+
+(define (get-timestamp path)
+  (file-or-directory-modify-seconds path #f (lambda () -inf.0)))
+
+(define (check-latest mod)
+  (let ([mpi (module-path-index-join mod #f)]
+        [done (make-hash)])
+    (let loop ([mpi mpi])
+      (let* ([rpath (module-path-index-resolve mpi)]
+             [path (resolved-module-path-name rpath)])
+        (when (path? path)
+         (let ([path (normal-case-path path)])
+            (unless (hash-ref done path #f)
+              (hash-set! done path #t)
+              (let ([mod (hash-ref loaded path #f)])
+                (when mod
+                  (for-each loop (mod-depends mod))
+                  (let ([ts (get-timestamp path)])
+                    (when (ts . > . (mod-timestamp mod))
+                      (let ([orig (current-load/use-compiled)])
+                        (parameterize ([current-load/use-compiled
+                                        (enter-load/use-compiled orig #f)]
+                                       [current-module-declare-name rpath])
+                          ((enter-load/use-compiled orig #t)
+                           path
+                           (mod-name mod)))))))))))))))
+
+;;; enter.rkt ends here
diff --git a/geiser/eval.rkt b/geiser/eval.rkt
new file mode 100644
index 0000000..e0bcffa
--- /dev/null
+++ b/geiser/eval.rkt
@@ -0,0 +1,81 @@
+;;; eval.rkt -- evaluation
+
+;; Copyright (C) 2009, 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Sun Apr 26, 2009 00:44
+
+#lang racket
+
+(provide eval-in
+         compile-in
+         load-file
+         compile-file
+         macroexpand
+         make-repl-reader)
+
+(require scheme/enter geiser/modules geiser/autodoc)
+
+(define last-result (void))
+
+(define namespace->module-name
+  (compose module-path-name->name namespace->module-path-name))
+
+(define last-namespace (make-parameter (current-namespace)))
+
+(define (exn-key e)
+  (vector-ref (struct->vector e) 0))
+
+(define (set-last-error e)
+  (set! last-result `((error (key . ,(exn-key e)))))
+  (display (exn-message e)))
+
+(define (write-value v)
+  (with-output-to-string
+    (lambda () (write v))))
+
+(define (set-last-result . vs)
+  (set! last-result `((result  ,@(map write-value vs)))))
+
+(define (call-with-result thunk)
+  (set-last-result (void))
+  (let ((output
+         (with-output-to-string
+           (lambda ()
+             (with-handlers ((exn? set-last-error))
+               (call-with-values thunk set-last-result))))))
+    (append last-result `((output . ,output)))))
+
+(define (eval-in form spec lang)
+  (call-with-result
+   (lambda ()
+     (update-signature-cache spec form)
+     (eval form (module-spec->namespace spec lang)))))
+
+(define compile-in eval-in)
+
+(define (load-file file)
+  (call-with-result
+   (lambda ()
+     (load-module file (current-output-port) (last-namespace))
+     (update-signature-cache file))))
+
+(define compile-file load-file)
+
+(define (macroexpand form . all)
+  (let ((all (and (not (null? all)) (car all))))
+    (with-output-to-string
+      (lambda ()
+        (pretty-print (syntax->datum ((if all expand expand-once) form)))))))
+
+(define (make-repl-reader builtin-reader)
+  (lambda (ns)
+    (last-namespace ns)
+    (printf "racket@~a" (namespace->module-name ns))
+    (builtin-reader)))
+
+;;; eval.rkt ends here
diff --git a/geiser/locations.rkt b/geiser/locations.rkt
new file mode 100644
index 0000000..b4c0f37
--- /dev/null
+++ b/geiser/locations.rkt
@@ -0,0 +1,54 @@
+;;; locations.rkt -- locating symbols
+
+;; Copyright (C) 2009, 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Sun Apr 26, 2009 19:43
+
+#lang racket
+
+(provide symbol-location
+         symbol-location*
+         module-location
+         symbol-module-name
+         symbol-module-path-name)
+
+(require geiser/utils geiser/modules)
+
+(define (symbol-location* sym)
+  (let* ((id (namespace-symbol->identifier sym))
+         (binding (and id (identifier-binding id))))
+    (if (list? binding)
+        (cons
+         (cadr binding)
+         (resolved-module-path-name
+          (module-path-index-resolve (car binding))))
+        (cons sym #f))))
+
+(define (make-location name path line)
+  (list (cons 'name name)
+        (cons 'file (if (path? path) (path->string path) '()))
+        (cons 'line (or line '()))))
+
+(define (symbol-location sym)
+  (let* ((loc (symbol-location* sym))
+         (name (car loc))
+         (path (cdr loc)))
+    (if path
+        (make-location name path #f)
+        (module-location sym))))
+
+(define symbol-module-path-name (compose cdr symbol-location*))
+
+(define symbol-module-name
+  (compose module-path-name->name symbol-module-path-name))
+
+(define (module-location sym)
+  (make-location sym (module-spec->path-name sym) 1))
+
+
+;;; locations.rkt ends here
diff --git a/geiser/main.rkt b/geiser/main.rkt
new file mode 100644
index 0000000..de1c21c
--- /dev/null
+++ b/geiser/main.rkt
@@ -0,0 +1,47 @@
+;;; main.rkt -- exported interface for emacs
+
+;; Copyright (C) 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Wed Mar 31, 2010 21:14
+
+#lang racket/base
+
+(provide geiser:eval
+         geiser:compile
+         geiser:load-file
+         geiser:compile-file
+         geiser:macroexpand
+         geiser:completions
+         geiser:module-completions
+         geiser:symbol-location
+         geiser:module-location
+         geiser:module-exports
+         geiser:autodoc
+         geiser:help)
+
+(require geiser/eval
+         geiser/modules
+         geiser/completions
+         geiser/locations
+         geiser/autodoc)
+
+(define (geiser:eval lang)
+  (lambda (form spec) (eval-in form spec lang)))
+(define geiser:compile compile-in)
+(define geiser:load-file load-file)
+(define geiser:compile-file compile-file)
+(define geiser:autodoc autodoc)
+(define geiser:help get-help)
+(define geiser:completions symbol-completions)
+(define geiser:module-completions module-completions)
+(define geiser:symbol-location symbol-location)
+(define geiser:module-location module-location)
+(define geiser:module-exports module-exports)
+(define geiser:macroexpand macroexpand)
+
+;;; main.rkt ends here
diff --git a/geiser/modules.rkt b/geiser/modules.rkt
new file mode 100644
index 0000000..0de316c
--- /dev/null
+++ b/geiser/modules.rkt
@@ -0,0 +1,150 @@
+;;; modules.rkt -- module metadata
+
+;; Copyright (C) 2009, 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Wed May 06, 2009 02:35
+
+#lang racket
+
+(provide load-module
+         ensure-module-spec
+         module-spec->namespace
+         namespace->module-path-name
+         module-path-name->name
+         module-spec->path-name
+         module-list
+         module-exports)
+
+(require srfi/13 syntax/modresolve syntax/modcode geiser/enter)
+
+(define (ensure-module-spec spec)
+  (cond ((symbol? spec) spec)
+        ((not (string? spec)) #f)
+        (else `(file ,spec))))
+
+(define (module-spec->namespace spec (lang #f))
+  (let ((spec (ensure-module-spec spec))
+        (try-lang (lambda (_)
+                    (with-handlers ((exn? (const (current-namespace))))
+                      (and lang
+                           (begin
+                             (load-module lang #f (current-namespace))
+                             (module->namespace lang)))))))
+    (or (and spec
+             (with-handlers ((exn? try-lang)) (get-namespace spec)))
+        (current-namespace))))
+
+(define nowhere (open-output-nowhere))
+
+(define (load-module spec (port #f) (ns #f))
+  (parameterize ((current-error-port (or port nowhere)))
+    (enter-module (ensure-module-spec spec))
+    (when (namespace? ns)
+      (current-namespace ns))))
+
+(define (namespace->module-path-name ns)
+  (let ((rmp (variable-reference->resolved-module-path
+              (eval '(#%variable-reference) ns))))
+    (and (resolved-module-path? rmp)
+         (resolved-module-path-name rmp))))
+
+(define (module-spec->path-name spec)
+  (with-handlers ((exn? (lambda (_) #f)))
+    (let ((ns (module-spec->namespace (ensure-module-spec spec))))
+      (namespace->module-path-name ns))))
+
+(define (module-path-name->name path)
+  (cond ((path? path)
+         (let* ((path (path->string path))
+                (cpaths (map (compose path->string path->directory-path)
+                             (current-library-collection-paths)))
+                (prefix-len (lambda (p)
+                              (let ((pl (string-length p)))
+                                (if (= pl (string-prefix-length p path))
+                                    pl
+                                    0))))
+                (lens (map prefix-len cpaths))
+                (real-path (substring path (apply max lens))))
+           (if (absolute-path? real-path)
+               (call-with-values (lambda () (split-path path))
+                 (lambda (_ basename __) (path->string basename)))
+               (regexp-replace "\\.[^./]*$" real-path ""))))
+        ((eq? path '#%kernel) "(kernel)")
+        ((string? path) path)
+        ((symbol? path) (symbol->string path))
+        (else "")))
+
+(define (skippable-dir? path)
+  (call-with-values (lambda () (split-path path))
+    (lambda (_ basename __)
+      (member (path->string basename) '(".svn" "compiled")))))
+
+(define path->symbol (compose string->symbol path->string))
+
+(define (path->entry path)
+  (let ((ext (filename-extension path)))
+    (and ext
+         (or (bytes=? ext #"rkt") (bytes=? ext #"ss"))
+         (let ((path (path->string path)))
+           (substring path 0 (- (string-length path) 3))))))
+
+(define (visit-module-path path kind acc)
+  (case kind
+    ((file) (let ((entry (path->entry path)))
+              (if entry (cons entry acc) acc)))
+    ((dir) (cond ((skippable-dir? path) (values acc #f))
+                 ((or (file-exists? (build-path path "main.rkt"))
+                      (file-exists? (build-path path "main.ss")))
+                  (cons (path->string path) acc))
+                 (else acc)))
+    (else acc)))
+
+(define (find-modules path acc)
+  (if (directory-exists? path)
+      (parameterize ((current-directory path))
+        (fold-files visit-module-path acc))
+      acc))
+
+(define (known-modules)
+  (sort (foldl find-modules '() (current-library-collection-paths)) string<?))
+
+(define module-cache #f)
+(define (update-module-cache)
+  (when (not module-cache) (set! module-cache (known-modules))))
+
+(define (module-list)
+  (update-module-cache)
+  module-cache)
+
+(define (module-exports mod)
+  (define (extract-ids ls)
+    (append-map (lambda (idls)
+                  (map car (cdr idls)))
+                ls))
+  (define (classify-ids ids ns)
+    (let loop ((ids ids) (procs '()) (vars '()))
+      (cond ((null? ids)
+             `((procs ,@(reverse procs)) (vars ,@(reverse vars))))
+            ((procedure?
+              (namespace-variable-value (car ids) #t (const #f) ns))
+             (loop (cdr ids) (cons (car ids) procs) vars))
+            (else (loop (cdr ids) procs (cons (car ids) vars))))))
+  (let-values (((reg syn)
+                (module-compiled-exports
+                 (get-module-code (resolve-module-path mod #f)))))
+    (let ((syn (extract-ids syn))
+          (reg (extract-ids reg)))
+      `((syntax ,@syn) ,@(classify-ids reg (module-spec->namespace mod))))))
+
+(define (startup)
+ (thread update-module-cache)
+ (void))
+
+(startup)
+
+;;; modules.rkt ends here
diff --git a/geiser/user.rkt b/geiser/user.rkt
new file mode 100644
index 0000000..3c1d93e
--- /dev/null
+++ b/geiser/user.rkt
@@ -0,0 +1,56 @@
+;;; user.rkt -- global bindings visible to geiser users
+
+;; Copyright (C) 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Wed Mar 31, 2010 22:24
+
+#lang racket/base
+
+(provide enter!)
+
+(require geiser/enter geiser/eval (for-syntax scheme/base))
+
+(define-syntax (enter! stx)
+  (syntax-case stx ()
+    [(enter! mod)
+     (if (or (not (syntax-e #'mod))
+             (module-path? (syntax->datum #'mod)))
+         #'(do-enter! 'mod)
+         (raise-syntax-error
+          #f
+          "not a valid module path, and not #f"
+          stx
+          #'mod))]
+    [_ (raise-syntax-error
+        #f
+        "bad syntax; should be `(enter! <module-path-or-#f>)'"
+        stx)]))
+
+(define orig-namespace (current-namespace))
+
+(define (do-enter! mod)
+  (if mod
+      (begin
+        (enter-module mod)
+        (let ([ns (module->namespace mod)])
+          (current-namespace ns)
+          (namespace-require 'geiser/user)))
+      (current-namespace orig-namespace)))
+
+
+(define orig-loader (current-load/use-compiled))
+
+(define (init)
+  (compile-enforce-module-constants #f)
+  (current-load/use-compiled (module-loader orig-loader))
+  (current-prompt-read (compose (make-repl-reader (current-prompt-read))
+                                current-namespace)))
+
+(init)
+
+;;; user.rkt ends here
diff --git a/geiser/utils.rkt b/geiser/utils.rkt
new file mode 100644
index 0000000..730a396
--- /dev/null
+++ b/geiser/utils.rkt
@@ -0,0 +1,27 @@
+;;; utils.rkt -- generic utilities
+
+;; Copyright (C) 2009, 2010 Jose Antonio Ortega Ruiz
+
+;; This program is free software; you can redistribute it and/or
+;; modify it under the terms of the Modified BSD License. You should
+;; have received a copy of the license along with this program. If
+;; not, see <http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5>.
+
+;; Start date: Sun May 03, 2009 03:09
+
+#lang racket
+
+(provide pair->list
+         keyword->symbol
+         symbol->keyword)
+
+(define (pair->list pair)
+  (let loop ((d pair) (s '()))
+    (cond ((null? d) (reverse s))
+          ((symbol? d) (reverse (cons d s)))
+          (else (loop (cdr d) (cons (car d) s))))))
+
+(define keyword->symbol (compose string->symbol keyword->string))
+(define (symbol->keyword sym) (string->keyword (format "~a" sym)))
+
+;;; utils.rkt ends here