guile 2.2: program-arities and program-module reloaded

Those two procedures are gone in these 2.2 times, and things like
autodoc and xref were broken as a result.  With Andy's help,
apparently good enough approximations of their functionality are now
in place: let's see how they go.

1 files changed, 28 insertions, 1 deletions

diff --git a/geiser/modules.scm b/geiser/modules.scm
index 780d39e..32b0f1f 100644
--- a/geiser/modules.scm
+++ b/geiser/modules.scm
@@ -1,6 +1,6 @@
 ;;; modules.scm -- module metadata
 
-;; Copyright (C) 2009, 2010, 2011 Jose Antonio Ortega Ruiz
+;; Copyright (C) 2009, 2010, 2011, 2018 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
@@ -11,6 +11,7 @@
 
 (define-module (geiser modules)
   #:export (symbol-module
+            program-module
             module-name?
             module-path
             find-module
@@ -19,10 +20,36 @@
             module-location)
   #:use-module (geiser utils)
   #:use-module (system vm program)
+  #:use-module (system vm debug)
   #:use-module (ice-9 regex)
   #:use-module (ice-9 session)
   #:use-module (srfi srfi-1))
 
+;; Return hash table mapping filename to list of modules defined in that
+;; file. H/t andy wingo.
+(define (fill-file->module-mapping! ret)
+  (define (record-module m)
+    (let ((f (module-filename m)))
+      (hash-set! ret f (cons m (hash-ref ret f '())))))
+  (define (visit-module m)
+    (record-module m)
+    (hash-for-each (lambda (k v) (visit-module v))
+                   (module-submodules m)))
+  (visit-module (resolve-module '() #f))
+  ret)
+
+(define file->modules (fill-file->module-mapping! (make-hash-table)))
+
+(define (program-file p)
+  (let ((src (program-source p 0)))
+    (and (pair? src) (cadr src))))
+
+(define (program-module p)
+  (let* ((f (program-file p))
+         (mods (or (hash-ref file->modules f)
+                   (hash-ref (fill-file->module-mapping! file->modules) f))))
+    (and (pair? mods) (not (null? mods)) (car mods))))
+
 (define (module-name? module-name)
   (and (list? module-name)
        (not (null? module-name))