List version of reduce

[jscl.git] / src / sequence.lisp

diff --git a/src/sequence.lisp b/src/sequence.lisp
index 8d2701b..789a7c3 100644 (file)
--- a/src/sequence.lisp
+++ b/src/sequence.lisp
@@ -33,14 +33,11 @@
              (let ((,elt (aref ,nseq ,index)))
                ,@body))))))
 
              (let ((,elt (aref ,nseq ,index)))
                ,@body))))))
 

-(defun find (item seq &key key (test #'eql))
-  (if key
-      (do-sequence (x seq)
-        (when (funcall test (funcall key x) item)
-          (return x)))
-      (do-sequence (x seq)
-        (when (funcall test x item)
-          (return x)))))
+(defun find (item seq &key key (test #'eql testp) (test-not #'eql test-not-p))
+  (do-sequence (x seq)
+    (when (satisfies-test-p item x :key key :test test :testp testp
+                            :test-not test-not :test-not-p test-not-p)
+      (return x))))

 
 (defun find-if (predicate sequence &key key)
   (if key
 
 (defun find-if (predicate sequence &key key)
   (if key

@@ -51,12 +48,38 @@
         (when (funcall predicate x)
           (return x)))))
 
         (when (funcall predicate x)
           (return x)))))
 

-(defun position (elt sequence &key (test #'eql))
-  (do-sequence (x seq index)
-    (when (funcall test elt x)
-      (return index))))
+(defun position (elt sequence
+                 &key key (test #'eql testp)
+                   (test-not #'eql test-not-p)
+                   (start 0) end)
+  ;; TODO: Implement START and END efficiently for all the sequence
+  ;; functions.
+  (let ((end (or end (length sequence))))
+    (do-sequence (x sequence index)
+      (when (and (<= start index)
+                 (< index end)
+                 (satisfies-test-p elt x
+                                   :key key :test test :testp testp
+                                   :test-not test-not :test-not-p test-not-p))
+        (return index)))))
+
+;; TODO: need to support &key from-end
+(defun position-if (predicate sequence
+                 &key key (start 0) end)
+  ;; TODO: Implement START and END efficiently for all the sequence
+  ;; functions.
+  (let ((end (or end (length sequence))))
+    (do-sequence (x sequence index)
+      (when (and (<= start index)
+                 (< index end)
+                 (funcall predicate (if key (funcall key x) x)))
+        (return index)))))

 
 

-(defun remove (x seq)
+(defun position-if-not (predicate sequence
+                 &key key (start 0) end)
+  (position-if (complement predicate) sequence :key key :start start :end end))
+
+(defun remove (x seq &key key (test #'eql testp) (test-not #'eql test-not-p))

   (cond
     ((null seq)
      nil)
   (cond
     ((null seq)
      nil)

@@ -64,7 +87,8 @@
      (let* ((head (cons nil nil))
             (tail head))
        (do-sequence (elt seq)
      (let* ((head (cons nil nil))
             (tail head))
        (do-sequence (elt seq)

-         (unless (eql x elt)
+         (unless (satisfies-test-p x elt :key key :test test :testp testp
+                                   :test-not test-not :test-not-p test-not-p)

            (let ((new (list elt)))
              (rplacd tail new)
              (setq tail new))))
            (let ((new (list elt)))
              (rplacd tail new)
              (setq tail new))))

@@ -72,7 +96,8 @@
     (t
      (let (vector)
        (do-sequence (elt seq index)
     (t
      (let (vector)
        (do-sequence (elt seq index)

-         (if (eql x elt)
+         (if (satisfies-test-p x elt :key key :test test :testp testp
+                               :test-not test-not :test-not-p test-not-p)

              ;; Copy the beginning of the vector only when we find an element
              ;; that does not match.
              (unless vector
              ;; Copy the beginning of the vector only when we find an element
              ;; that does not match.
              (unless vector

@@ -129,7 +154,7 @@
      (if b
        (let ((diff (- b a)))
          (cond
      (if b
        (let ((diff (- b a)))
          (cond

-           ((zerop  diff) ()) 
+           ((zerop  diff) ())

            ((minusp diff)
             (error "Start index must be smaller than end index"))
            (t
            ((minusp diff)
             (error "Start index must be smaller than end index"))
            (t

@@ -139,11 +164,42 @@
                 (setq pointer (cdr pointer))
                 (when (null pointer)
                   (error "Ending index larger than length of list")))
                 (setq pointer (cdr pointer))
                 (when (null pointer)
                   (error "Ending index larger than length of list")))

-              (rplacd pointer ()) 
+              (rplacd pointer ())

               drop-a))))
        (copy-list (nthcdr a seq))))
               drop-a))))
        (copy-list (nthcdr a seq))))

-    ((arrayp seq) 
-     (if b
-       (slice seq a b)
-       (slice seq a)))
+    ((vectorp seq)
+     (let* ((b (or b (length seq)))
+            (size (- b a))
+            (new (make-array size :element-type (array-element-type seq))))
+       (do ((i 0 (1+ i))
+            (j a (1+ j)))
+           ((= j b) new)
+         (aset new i (aref seq j)))))

     (t (not-seq-error seq))))
     (t (not-seq-error seq))))

+
+(defun copy-seq (sequence)
+  (subseq sequence 0))
+
+;;; Based on the SBCL's reduce implementation
+(defun reduce (function sequence &key key from-end (start 0) end (initial-value nil ivp))
+  (let ((key (or key #'identity))
+        (end (or end (length sequence))))
+    (if (= end start)
+        (if ivp initial-value (funcall function))
+        (if from-end
+            (let ((sequence (nthcdr (- (length sequence) end) (reverse sequence))))
+              (do ((count (if ivp start (1+ start))
+                          (1+ count))
+                   (sequence (if ivp sequence (cdr sequence))
+                             (cdr sequence))
+                   (value (if ivp initial-value (funcall key (car sequence)))
+                          (funcall function (funcall key (car sequence)) value)))
+                  ((>= count end) value)))
+            (let ((sequence (nthcdr start sequence)))
+              (do ((count (if ivp start (1+ start))
+                          (1+ count))
+                   (sequence (if ivp sequence (cdr sequence))
+                             (cdr sequence))
+                   (value (if ivp initial-value (funcall key (car sequence)))
+                          (funcall function value (funcall key (car sequence)))))
+                  ((>= count end) value)))))))