1 files changed, 17 insertions, 24 deletions
diff --git a/module/c/cpp-environment.scm b/module/c/cpp-environment.scm
index 39e596d1..da8e4413 100644
--- a/module/c/cpp-environment.scm
+++ b/module/c/cpp-environment.scm
@@ -1,7 +1,6 @@
 (define-module (c cpp-environment)
   :use-module (srfi srfi-1)
   :use-module (srfi srfi-88)
-  :use-module (ice-9 hash-table)
   :use-module ((hnh util) :select (->>))
   :use-module (hnh util object)
   :use-module (hnh util type)
@@ -18,7 +17,6 @@
            macro-identifier-list
            macro-variadic?
            cpp-macro?
-           ;; pprint-macro
 
            enter-into-if
            transition-to-if
@@ -39,10 +37,8 @@
            object-macro?
            internal-macro?
 
-           cpp-environment
            cpp-environment?
            cpp-if-status
-           ;; cpp-variables
            cpp-file-stack
 
            make-environment in-environment?
@@ -108,10 +104,8 @@
   (cpp-if-status type: (and (list-of if-status?)
                             (not null?))
                  default: (list (if-status outside)))
-  ;; not exported since type signatures don't hold inside the hash table
-  ;; TODO replace hash table with something that doesn't require copying the
-  ;; entire structure every time
-  (cpp-variables type: hash-table? default: (make-hash-table))
+  (cpp-variables type: (alist-of string? cpp-macro?)
+                 default: '())
   (cpp-file-stack type: (and (not null?)
                              (list-of (pair-of string? exact-integer?)))
                   default: '(("*outside*" . 1))))
@@ -208,32 +202,31 @@
 
 (define (make-environment) (cpp-environment))
 
-(define (clone-hash-table ht)
-  (alist->hash-table (hash-map->list cons ht)))
+;; (define (clone-hash-table ht)
+;;   (alist->hash-table (hash-map->list cons ht)))
 
-(define (clone-environment environment)
-  (modify environment cpp-variables clone-hash-table))
+;; (define (clone-environment environment)
+;;   (modify environment cpp-variables clone-hash-table))
 
 (define (in-environment? environment key)
-  (hash-get-handle (cpp-variables environment) key))
+  (assoc key (cpp-variables environment)))
 
 (define (remove-identifier environment key)
   (typecheck key string?)
 
-  (let ((environment (clone-environment environment)))
-    (hash-remove! (cpp-variables environment) key)
-    environment))
+  (modify environment cpp-variables
+          (lambda (vars) (remove (lambda (slot) (string=? key (car slot)))
+                            vars))))
 
 (define (add-identifier environment key value)
   (typecheck key string?)
   (typecheck value cpp-macro?)
 
-  (let ((environment (clone-environment environment)))
-    (hash-set! (cpp-variables environment) key value)
-    environment))
+  (modify environment cpp-variables
+          (lambda (vars) (acons key value vars))))
 
 (define (get-identifier environment key)
-  (hash-ref (cpp-variables environment) key))
+  (assoc-ref (cpp-variables environment) key))
 
 
 (define (extend-environment environment macros)
@@ -250,10 +243,10 @@
 
 (define* (pprint-environment environment optional: (port (current-error-port)))
   (display "== Environment ==\n" port)
-  (hash-for-each (lambda (key macro)
-                   (pprint-macro macro port)
-                   (newline port))
-                 (cpp-variables environment)))
+  (for-each (lambda (pair)
+              (pprint-macro (cdr pair) port)
+              (newline port))
+            (cpp-variables environment)))
 
 (define* (pprint-macro x optional: (p (current-output-port)))
   (cond ((internal-macro? x)