[lazy] got rid of Sequence, (seq iseq) no longer an identity, ISeqs can be empty, PersistentList.EMPTY and LazySeq.EMPTY are ISeqs, rest returns ISeq

Author: richhickey

src/clj/clojure/core.clj

@@ -96,7 +96,7 @@
 
 (def
  #^{:arglists '([coll])
-    :doc "Sequence. Returns a new ISeq on the collection. If the
+    :doc "Returns a new ISeq on the collection. If the
     collection is empty, returns nil.  (seq nil) returns nil. seq also
     works on Strings, native Java arrays (of reference types) and any
     objects that implement Iterable."
@@ -114,11 +114,6 @@
     :doc "Return true if x implements ISeq"}
  seq? (fn seq? [x] (instance? clojure.lang.ISeq x)))
 
-(def
- #^{:arglists '([x])
-    :doc "Return true if x implements Sequence, true of ISeqs and LazySeqs"}
- sequence? (fn sequence? [x] (instance? clojure.lang.Sequence x)))
-
 (def
  #^{:arglists '([x])
     :doc "Return true if x is a String"}
@@ -138,7 +133,7 @@
  #^{:private true}
  sigs
  (fn [fdecl]
-   (if (sequence? (first fdecl))
+   (if (seq? (first fdecl))
      (loop [ret [] fdecl fdecl]
        (if fdecl
          (recur (conj ret (first (first fdecl))) (next fdecl))
@@ -185,7 +180,7 @@
 
 (def 
  #^{:arglists '([coll])
-    :doc "Return a sequence of all but the last item in coll, in linear time"}
+    :doc "Return a seq of all but the last item in coll, in linear time"}
  butlast (fn butlast [s]
            (loop [ret [] s s]
              (if (next s)
@@ -430,7 +425,7 @@
     (list* '#^{:once true :super-name "clojure/lang/LazySeq"} fn* [] body))
 
 (defn concat
-  "Returns a lazy sequence representing the concatenation of the elements in the supplied colls."
+  "Returns a lazy seq representing the concatenation of the elements in the supplied colls."
   ([] (lazy-seq nil))
   ([x] (lazy-seq x))
   ([x y]
@@ -971,8 +966,8 @@
     (. e (getValue)))
 
 (defn rseq
-  "Returns, in constant time, a sequence of the items in rev (which
-  can be a vector or sorted-map), in reverse order."
+  "Returns, in constant time, a seq of the items in rev (which
+  can be a vector or sorted-map), in reverse order. If rev is empty returns nil"
   [#^clojure.lang.Reversible rev]
     (. rev (rseq)))
 
@@ -1021,7 +1016,7 @@
   second item in the first form, making a list of it if it is not a
   list already. If there are more forms, inserts the first form as the
   second item in second form, etc."
-  ([x form] (if (sequence? form)
+  ([x form] (if (seq? form)
               `(~(first form) ~x ~@(next form))
               (list form x)))
   ([x form & more] `(-> (-> ~x ~form) ~@more)))
@@ -2080,7 +2075,7 @@
     (let [gx (gensym)]
       `(let [~gx ~x]
          ~@(map (fn [f]
-                  (if (sequence? f)
+                  (if (seq? f)
                     `(~(first f) ~gx ~@(next f))
                     `(~f ~gx)))
                 forms)

src/clj/clojure/core_print.clj

@@ -128,18 +128,18 @@
 (defmethod print-dup clojure.lang.Var [#^clojure.lang.Var o, #^Writer w]
   (.write w (str "#=(var " (.name (.ns o)) "/" (.sym o) ")")))
 
-(defmethod print-method clojure.lang.Sequence [o, #^Writer w]
+(defmethod print-method clojure.lang.ISeq [o, #^Writer w]
   (print-meta o w)
   (print-sequential "(" pr-on " " ")" o w))
 
-(defmethod print-dup clojure.lang.Sequence [o w] (print-method o w))
+(defmethod print-dup clojure.lang.ISeq [o w] (print-method o w))
 (defmethod print-dup clojure.lang.IPersistentList [o w] (print-method o w))
-(prefer-method print-method clojure.lang.IPersistentList clojure.lang.Sequence)
-(prefer-method print-dup clojure.lang.IPersistentList clojure.lang.Sequence)
-(prefer-method print-method clojure.lang.Sequence clojure.lang.IPersistentCollection)
-(prefer-method print-dup clojure.lang.Sequence clojure.lang.IPersistentCollection)
-(prefer-method print-method clojure.lang.Sequence java.util.Collection)
-(prefer-method print-dup clojure.lang.Sequence java.util.Collection)
+(prefer-method print-method clojure.lang.IPersistentList clojure.lang.ISeq)
+(prefer-method print-dup clojure.lang.IPersistentList clojure.lang.ISeq)
+(prefer-method print-method clojure.lang.ISeq clojure.lang.IPersistentCollection)
+(prefer-method print-dup clojure.lang.ISeq clojure.lang.IPersistentCollection)
+(prefer-method print-method clojure.lang.ISeq java.util.Collection)
+(prefer-method print-dup clojure.lang.ISeq java.util.Collection)
 
 (defmethod print-method clojure.lang.IPersistentList [o, #^Writer w]
   (print-meta o w)

src/jvm/clojure/lang/ASeq.java

@@ -110,7 +110,7 @@ public ISeq cons(Object o){
 	return new Cons(o, this);
 }
 
-public Sequence more(){
+public ISeq more(){
     ISeq s = next();
     if(s == null)
         return LazySeq.EMPTY;

src/jvm/clojure/lang/Cons.java

@@ -12,18 +12,18 @@
 
 package clojure.lang;
 
-public class Cons extends ASeq{
+final public class Cons extends ASeq{
 
 private final Object _first;
-private final Sequence _more;
+private final ISeq _more;
 
-public Cons(Object first, Sequence _more){
+public Cons(Object first, ISeq _more){
 	this._first = first;
 	this._more = _more;
 }
 
 
-public Cons(IPersistentMap meta, Object _first, Sequence _more){
+public Cons(IPersistentMap meta, Object _first, ISeq _more){
 	super(meta);
 	this._first = _first;
 	this._more = _more;
@@ -37,7 +37,7 @@ public ISeq next(){
 	return more().seq();
 }
 
-public Sequence more(){
+public ISeq more(){
 	if(_more == null)
 		return LazySeq.EMPTY;
 	return _more;