Merge pull request #2 from arvyy/master

Create library, rewrite tests against external api, add alist, plist and srfi69/125 implementation

1 files changed, 72 insertions, 0 deletions

diff --git a/alist-impl.scm b/alist-impl.scm
new file mode 100644
index 0000000..fab350d
--- /dev/null
+++ b/alist-impl.scm
@@ -0,0 +1,72 @@
+(define (register-alist!)
+  
+  (define (alist? l)
+    (and (list? l)
+         (or (null? l)
+             (pair? (car l)))))
+
+  (define (alist-map! proc alist)
+    (map 
+      (lambda (e)
+        (define key (car e))
+        (define value (cdr e))
+        (cons key (proc key value))) 
+      alist))
+
+  (define (alist-filter! pred alist)
+    (filter
+      (lambda (e)
+        (pred (car e) (cdr e))) 
+      alist))
+
+  (define (alist-search! alist key failure success)
+    (define (handle-success pair)
+      (define old-key (car pair))
+      (define old-value (cdr pair))
+      (define (update new-key new-value obj)
+        (cond 
+          ((and (eq? old-key
+                     new-key)
+                (eq? old-value
+                     new-value))
+           (values alist obj))
+          (else
+            (let ((new-list 
+                    (alist-cons
+                      new-key new-value
+                      (alist-delete old-key alist))))
+              (values new-list obj)))))
+      (define (remove obj)
+        (values (alist-delete old-key alist) obj))
+      (success old-key old-value update remove))
+
+    (define (handle-failure)
+      (define (insert value obj)
+        (values (alist-cons key value alist)
+                obj))
+      (define (ignore obj)
+        (values alist obj))
+      (failure insert ignore))
+    (cond
+      ((assoc key alist) => handle-success)
+      (else (handle-failure))))
+
+  (define (alist-size alist)
+    (length alist))
+
+  (define (alist-foreach proc alist)
+    (define (proc* e)
+      (proc (car e) (cdr e)))
+    (for-each proc* alist))
+  
+  (define (alist->alist alist)
+    alist)
+
+  (register-dictionary! 
+    'dictionary? alist?
+    'dict-map! alist-map!
+    'dict-filter! alist-filter!
+    'dict-search! alist-search!
+    'dict-size alist-size
+    'dict-for-each alist-foreach
+    'dict->alist alist->alist))