Attached is an updated patch. Instead of using "for" in the
implementation of "doseq", this has a "doseq" that uses loop/recure.
The interface is the same, but it should run faster. This also means
"doseq" is only defined once (nor redefined as in the earlier patch).
This patch is against 1089, the "Interim checkin - DO NOT USE!!" version of SVN.
--Chouser
On Sat, Nov 8, 2008 at 7:42 AM, Rich Hickey <[EMAIL PROTECTED]> wrote:
>
>
>
> On Nov 7, 5:09 pm, James Reeves <[EMAIL PROTECTED]> wrote:
>> On Nov 7, 9:32 pm, Chouser <[EMAIL PROTECTED]> wrote:
>>
>> > > And in which case, your vector syntax could be misleading, because it
>> > > seems to imply you're assigning i to 10:
>>
>> > > (dotimes [i 10]
>> > > (prn i))
>>
>> > Vectors are also used for "for":
>>
>> > (for [i (range 10)]
>> > (* 2 i))
>>
>> > Here i is not bound to the seq (range 10) but to each of the numbers
>> > in turn.
>>
>> I'm still not convinced on this one. Currently, you have single
>> assignments, where a value is assigned to a symbol as in let and
>> binding, and sequence assignments, where each item in the sequence is
>> assigned to a symbol. Adding a vector to dotimes would add a third
>> type, and I don't think it's obvious what the [i 10] does. I mean, you
>> originally put it down as [i (range 10)], so you were thinking in
>> terms of [symbol sequence] too.
>>
>
> The general idea behind this patch is that all macros that introduce
> names will do so in vector syntax. The nature of the bindings is going
> to be open, as is the set of macros - doseq/dotimes/let/loop all have
> different semantics. As it stands, it is confusing for people because
> they don't know if they need a vector or not, for each macro.
>
>> > > Second, with your patch, is the following valid:
>>
>> > > (doseq [i (range 10)
>> > > j (range 10)]
>> > > (prn i)
>> > > (prn j))
>>
>> > It behaves the same as "for" does, that is with j in an inner loop.
>> > It also supports :while and :when as "for" does.
>>
>> Well, not that my opinion matters ;) - but you've sold me on this one.
>> Consistency with the for macro seems reasonable.
>>
>
> This is a much-needed enhancement, as so many people use for for side-
> effects and forget dorun. Plus it will be faster for that use.
>
>> > My first inclination is to disallow it -- add a check to make sure
>> > only one binding pair is given. Alternatively it could act as if it
>> > were nested, as "for" (and now "doseq") do, in which case it would act
>> > like an "and", and both x and y would be bound to non-false values.
>>
>> Hm. A nested if would be consistent with the nested for and doseq
>> macros. If this is implemented, nesting ifs would be my preference for
>> this.
>>
>
> I'd like to see this patch limit its enhancements to "doseq a la for",
> and otherwise just be a syntax change for all the others.
>
> Rich
>
> >
>
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-~----------~----~----~----~------~----~------~--~---
commit dfd51264b386c753eeda38e0cab20de97bdded94
Author: Chouser <[EMAIL PROTECTED]>
Date: Sat Nov 8 08:31:01 2008 -0500
Use vectors for bindings in doseq, et al.
diff --git a/src/clj/clojure/boot.clj b/src/clj/clojure/boot.clj
index e0d7450..0df3b89 100644
--- a/src/clj/clojure/boot.clj
+++ b/src/clj/clojure/boot.clj
@@ -1437,6 +1437,18 @@
([keyfn #^java.util.Comparator comp coll]
(sort (fn [x y] (. comp (compare (keyfn x) (keyfn y)))) coll)))
+(defn partition
+ "Returns a lazy sequence of lists of n items each, at offsets step
+ apart. If step is not supplied, defaults to n, i.e. the partitions
+ do not overlap."
+ ([n coll]
+ (partition n n coll))
+ ([n step coll]
+ (when (seq coll)
+ (let [p (take n coll)]
+ (when (= n (count p))
+ (lazy-cons p (partition n step (drop step coll))))))))
+
;; evaluation
(defn eval
@@ -1445,14 +1457,23 @@
(defmacro doseq
"Repeatedly executes body (presumably for side-effects) with
- binding-form bound to successive items from coll. Does not retain
+ bindings and filtering as provided by \"for\". Does not retain
the head of the sequence. Returns nil."
- [item list & body]
- `(loop [list# (seq ~list)]
- (when list#
- (let [~item (first list#)]
- [EMAIL PROTECTED])
- (recur (rest list#)))))
+ [seq-exprs & body]
+ (let [binds (reduce (fn [binds p]
+ (if (instance? clojure.lang.Keyword (first p))
+ (conj (pop binds) (apply assoc (peek binds) p))
+ (conj binds {:name (first p) :init (second p)})))
+ [] (partition 2 seq-exprs))
+ emit (fn emit [bind & binds]
+ `(loop [sq# (seq ~(:init bind))]
+ (when sq#
+ (let [~(:name bind) (first sq#)]
+ (when ~(or (:while bind) true)
+ (when ~(or (:when bind) true)
+ ~(if binds (apply emit binds) `(do [EMAIL PROTECTED])))
+ (recur (rest sq#)))))))]
+ (apply emit binds)))
(defn scan [& args] (throw (new Exception "scan is now called dorun")))
(defn touch [& args] (throw (new Exception "touch is now called doall")))
@@ -1493,7 +1514,7 @@
(throw (new Exception "Can't await in agent action")))
(let [latch (new java.util.concurrent.CountDownLatch (count agents))
count-down (fn [agent] (. latch (countDown)) agent)]
- (doseq agent agents
+ (doseq [agent agents]
(send agent count-down))
(. latch (await))))
@@ -1512,19 +1533,26 @@
(throw (new Exception "Can't await in agent action")))
(let [latch (new java.util.concurrent.CountDownLatch (count agents))
count-down (fn [agent] (. latch (countDown)) agent)]
- (doseq agent agents
+ (doseq [agent agents]
(send agent count-down))
(. latch (await timeout-ms (. java.util.concurrent.TimeUnit MILLISECONDS)))))
(defmacro dotimes
- "Repeatedly executes body (presumably for side-effects) with name
+ "bindings => name n
+
+ Repeatedly executes body (presumably for side-effects) with name
bound to integers from 0 through n-1."
- [i n & body]
- `(let [n# (int ~n)]
- (loop [~i (int 0)]
- (when (< ~i n#)
- [EMAIL PROTECTED]
- (recur (unchecked-inc ~i))))))
+ [bindings & body]
+ (if (vector? bindings)
+ (let [i (first bindings)
+ n (second bindings)]
+ `(let [n# (int ~n)]
+ (loop [~i (int 0)]
+ (when (< ~i n#)
+ [EMAIL PROTECTED]
+ (recur (unchecked-inc ~i))))))
+ (throw (IllegalArgumentException.
+ "dotimes now requires a vector for its binding"))))
(defn import
"import-list => (package-symbol class-name-symbols*)
@@ -1537,7 +1565,7 @@
(let [#^clojure.lang.Namespace ns *ns*
pkg (ffirst import-lists)
classes (rfirst import-lists)]
- (doseq c classes
+ (doseq [c classes]
(. ns (importClass c (. Class (forName (str pkg "." c)))))) )
(apply import (rest import-lists))))
@@ -1713,14 +1741,19 @@
[s] (clojure.lang.RT/readString s))
(defmacro with-open
- "Evaluates body in a try expression with name bound to the value of
- init, and a finally clause that calls (. name (close))."
- [name init & body]
- `(let [~name ~init]
- (try
- [EMAIL PROTECTED]
- (finally
- (. ~name (close))))))
+ "bindings => name init
+
+ Evaluates body in a try expression with name bound to the value of
+ init, and a finally clause that calls (.close name)."
+ [bindings & body]
+ (if (vector? bindings)
+ `(let ~bindings
+ (try
+ [EMAIL PROTECTED]
+ (finally
+ (.close ~(first bindings)))))
+ (throw (IllegalArgumentException.
+ "with-open now requires a vector for its binding"))))
(defmacro doto
"Evaluates x then calls all of the methods with the supplied
@@ -1844,7 +1877,7 @@
([#^Class type dim & more-dims]
(let [dims (cons dim more-dims)
#^"[I" dimarray (make-array (. Integer TYPE) (count dims))]
- (dotimes i (alength dimarray)
+ (dotimes [i (alength dimarray)]
(aset-int dimarray i (nth dims i)))
(. Array (newInstance type dimarray)))))
@@ -2003,7 +2036,7 @@
(.unmap (the-ns ns) sym))
;(defn export [syms]
-; (doseq sym syms
+; (doseq [sym syms]
; (.. *ns* (intern sym) (setExported true))))
(defn ns-publics
@@ -2042,7 +2075,7 @@
rename (or (:rename fs) {})
exclude (set (:exclude fs))
to-do (or (:only fs) (keys nspublics))]
- (doseq sym to-do
+ (doseq [sym to-do]
(when-not (exclude sym)
(let [v (nspublics sym)]
(when-not v
@@ -2278,11 +2311,17 @@
[EMAIL PROTECTED])))))))
(defmacro when-first
- "Same as (when (seq xs) (let [x (first xs)] body))"
- [x xs & body]
- `(when (seq ~xs)
- (let [~x (first ~xs)]
- [EMAIL PROTECTED])))
+ "bindings => x xs
+
+ Same as (when (seq xs) (let [x (first xs)] body))"
+ [bindings & body]
+ (if (vector? bindings)
+ (let [[x xs] bindings]
+ `(when (seq ~xs)
+ (let [~x (first ~xs)]
+ [EMAIL PROTECTED])))
+ (throw (IllegalArgumentException.
+ "when-first now requires a vector for its binding"))))
(defmacro lazy-cat
"Expands to code which yields a lazy sequence of the concatenation
@@ -2320,7 +2359,7 @@
emit (fn emit [[{b :b f :f w :w} & [{ys :e} :as rses]]]
(let [giter (gensym "iter__") gxs (gensym "s__")]
`(fn ~giter [~gxs]
- (when-first ~b ~gxs
+ (when-first [~b ~gxs]
(if ~f
~(if rses
`(let [iterys# ~(emit rses)
@@ -2534,7 +2573,7 @@
tree, must be a branch."
[branch? children root]
(let [walk (fn walk [nodes]
- (when-first node nodes
+ (when-first [node nodes]
(lazy-cons
node
(if (branch? node)
@@ -2571,7 +2610,7 @@
(defn slurp
"Reads the file named by f into a string and returns it."
[#^String f]
- (with-open r (new java.io.BufferedReader (new java.io.FileReader f))
+ (with-open [r (new java.io.BufferedReader (new java.io.FileReader f))]
(let [sb (new StringBuilder)]
(loop [c (. r (read))]
(if (neg? c)
@@ -2609,24 +2648,36 @@
(lazy-cons f (step r (conj seen f))))))]
(step (seq coll) #{})))
-(defmacro if-let
- "if test is true, evaluates then with binding-form bound to the value of test, if not, yields else"
- ([binding-form test then]
- `(if-let ~binding-form ~test ~then nil))
- ([binding-form test then else]
- `(let [temp# ~test]
- (if temp#
- (let [~binding-form temp#]
- ~then)
- ~else))))
-
-(defmacro when-let
- "when test is true, evaluates body with binding-form bound to the value of test"
- [binding-form test & body]
- `(let [temp# ~test]
- (when temp#
- (let [~binding-form temp#]
- [EMAIL PROTECTED]))))
+(defmacro if-let
+ "bindings => binding-form test
+
+ If test is true, evaluates then with binding-form bound to the value of test, if not, yields else"
+ ([bindings then]
+ `(if-let ~bindings ~then nil))
+ ([bindings then else & oldform]
+ (if (and (vector? bindings) (nil? oldform))
+ (let [[form tst] bindings]
+ `(let [temp# ~tst]
+ (if temp#
+ (let [~form temp#]
+ ~then)
+ ~else)))
+ (throw (IllegalArgumentException.
+ "if-let now requires a vector for its binding")))))
+
+(defmacro when-let
+ "bindings => binding-form test
+
+ When test is true, evaluates body with binding-form bound to the value of test"
+ [bindings & body]
+ (if (vector? bindings)
+ (let [[form tst] bindings]
+ `(let [temp# ~tst]
+ (when temp#
+ (let [~form temp#]
+ [EMAIL PROTECTED]))))
+ (throw (IllegalArgumentException.
+ "when-let now requires a vector for its binding"))))
(defn replace
"Given a map of replacement pairs and a vector/collection, returns a
@@ -2635,11 +2686,11 @@
[smap coll]
(if (vector? coll)
(reduce (fn [v i]
- (if-let e (find smap (nth v i))
+ (if-let [e (find smap (nth v i))]
(assoc v i (val e))
v))
coll (range (count coll)))
- (map #(if-let e (find smap %) (val e) %) coll)))
+ (map #(if-let [e (find smap %)] (val e) %) coll)))
(defmacro dosync
"Runs the exprs (in an implicit do) in a transaction that encompasses
@@ -2679,11 +2730,11 @@
([#^clojure.lang.Sorted sc test key]
(let [include (bound-fn sc test key)]
(if (#{> >=} test)
- (when-let [e :as s] (. sc seqFrom key true)
+ (when-let [[e :as s] (. sc seqFrom key true)]
(if (include e) s (rest s)))
(take-while include (. sc seq true)))))
([#^clojure.lang.Sorted sc start-test start-key end-test end-key]
- (when-let [e :as s] (. sc seqFrom start-key true)
+ (when-let [[e :as s] (. sc seqFrom start-key true)]
(take-while (bound-fn sc end-test end-key)
(if ((bound-fn sc start-test start-key) e) s (rest s))))))
@@ -2694,11 +2745,11 @@
([#^clojure.lang.Sorted sc test key]
(let [include (bound-fn sc test key)]
(if (#{< <=} test)
- (when-let [e :as s] (. sc seqFrom key false)
+ (when-let [[e :as s] (. sc seqFrom key false)]
(if (include e) s (rest s)))
(take-while include (. sc seq false)))))
([#^clojure.lang.Sorted sc start-test start-key end-test end-key]
- (when-let [e :as s] (. sc seqFrom end-key false)
+ (when-let [[e :as s] (. sc seqFrom end-key false)]
(take-while (bound-fn sc start-test start-key)
(if ((bound-fn sc end-test end-key) e) s (rest s))))))
@@ -2721,18 +2772,6 @@
"Returns a lazy seq of the elements of coll separated by sep"
[sep coll] (drop 1 (interleave (repeat sep) coll)))
-(defn partition
- "Returns a lazy sequence of lists of n items each, at offsets step
- apart. If step is not supplied, defaults to n, i.e. the partitions
- do not overlap."
- ([n coll]
- (partition n n coll))
- ([n step coll]
- (when (seq coll)
- (let [p (take n coll)]
- (when (= n (count p))
- (lazy-cons p (partition n step (drop step coll))))))))
-
(defmacro definline
"Experimental - like defmacro, except defines a named function whose
body is the expansion, calls to which may be expanded inline as if
@@ -3196,7 +3235,7 @@
(when use
(when *loading-verbosely*
(printf "(clojure/refer '%s" lib)
- (doseq opt filter-opts
+ (doseq [opt filter-opts]
(printf " %s '%s" (key opt) (print-str (val opt))))
(printf ")\n"))
(apply refer lib (mapcat seq filter-opts))))))
@@ -3208,12 +3247,12 @@
(let [flags (filter keyword? args)
opts (interleave flags (repeat true))
args (filter (complement keyword?) args)]
- (doseq arg args
+ (doseq [arg args]
(if (libspec? arg)
(apply load-lib nil (prependss arg opts))
(let [[prefix & args] arg]
(throw-if (nil? prefix) "prefix cannot be nil")
- (doseq arg args
+ (doseq [arg args]
(apply load-lib prefix (prependss arg opts))))))))
;; Public
@@ -3290,7 +3329,7 @@
classpath-relative if it begins with a slash or relative to the root
directory for the current namespace otherwise."
[& paths]
- (doseq path paths
+ (doseq [path paths]
(let [path (if (.startsWith path "/")
path
(str (root-directory (ns-name *ns*)) \/ path))]
@@ -3468,7 +3507,7 @@
(.write w "#")
(do
(.write w begin)
- (when-let xs (seq sequence)
+ (when-let [xs (seq sequence)]
(if (and (not *print-dup*) *print-length*)
(loop [[x & xs] xs
print-length *print-length*]
@@ -3487,7 +3526,7 @@
(.write w end)))))
(defn- print-meta [o, #^Writer w]
- (when-let m (meta o)
+ (when-let [m (meta o)]
(when (and (pos? (count m))
(or *print-dup*
(and *print-meta* *print-readably*)))
@@ -3607,7 +3646,7 @@
(defmethod print-method String [#^String s, #^Writer w]
(if (or *print-dup* *print-readably*)
(do (.append w \")
- (dotimes n (count s)
+ (dotimes [n (count s)]
(let [c (.charAt s n)
e (char-escape-string c)]
(if e (.write w e) (.append w c))))
diff --git a/src/clj/clojure/genclass.clj b/src/clj/clojure/genclass.clj
index d2d10a1..49e9ad4 100644
--- a/src/clj/clojure/genclass.clj
+++ b/src/clj/clojure/genclass.clj
@@ -232,7 +232,7 @@
(when-not as-static
(. gen (loadThis)))
;box args
- (dotimes i (count ptypes)
+ (dotimes [i (count ptypes)]
(. gen (loadArg i))
(. clojure.lang.Compiler$HostExpr (emitBoxReturn nil gen (nth pclasses i))))
;call fn
@@ -265,7 +265,7 @@
(into-array (map iname interfaces)))))
;static fields for vars
- (doseq v var-fields
+ (doseq [v var-fields]
(. cv (visitField (+ (. Opcodes ACC_PUBLIC) (. Opcodes ACC_FINAL) (. Opcodes ACC_STATIC))
(var-name v)
(. var-type getDescriptor)
@@ -283,7 +283,7 @@
(. Method getMethod "void <clinit> ()")
nil nil cv)]
(. gen (visitCode))
- (doseq v var-fields
+ (doseq [v var-fields]
(. gen push pkg-name)
(. gen push (str sname "-" v))
(. gen (invokeStatic rt-type (. Method (getMethod "clojure.lang.Var var(String,String)"))))
@@ -298,7 +298,7 @@
(. gen (endMethod)))
;ctors
- (doseq [pclasses super-pclasses] ctor-sig-map
+ (doseq [[pclasses super-pclasses] ctor-sig-map]
(let [ptypes (to-types pclasses)
super-ptypes (to-types super-pclasses)
m (new Method "<init>" (. Type VOID_TYPE) ptypes)
@@ -316,7 +316,7 @@
(. gen dup)
(. gen ifNull no-init-label)
;box init args
- (dotimes i (count pclasses)
+ (dotimes [i (count pclasses)]
(. gen (loadArg i))
(. clojure.lang.Compiler$HostExpr (emitBoxReturn nil gen (nth pclasses i))))
;call init fn
@@ -330,7 +330,7 @@
(. gen (loadThis))
(. gen dupX1)
- (dotimes i (count super-pclasses)
+ (dotimes [i (count super-pclasses)]
(. gen loadLocal local)
(. gen push i)
(. gen (invokeStatic rt-type nth-method))
@@ -373,7 +373,7 @@
;add methods matching supers', if no fn -> call super
(let [mm (non-private-methods super)]
- (doseq #^java.lang.reflect.Method meth (vals mm)
+ (doseq [#^java.lang.reflect.Method meth (vals mm)]
(emit-forwarding-method (.getName meth) (.getParameterTypes meth) (.getReturnType meth) false
(fn [gen m]
(. gen (loadThis))
@@ -394,7 +394,7 @@
(assoc mm (method-sig meth) meth))))
mm (mapcat #(.getMethods %) interfaces))
;extra methods
- (doseq [mname pclasses rclass :as msig] methods
+ (doseq [[mname pclasses rclass :as msig] methods]
(emit-forwarding-method (str mname) pclasses rclass (:static ^msig)
emit-unsupported)))
@@ -423,7 +423,7 @@
(. gen (returnValue))
(. gen (endMethod))))
;field exposers
- (doseq [f {getter :get setter :set}] exposes
+ (doseq [[f {getter :get setter :set}] exposes]
(let [fld (.getDeclaredField super (str f))
ftype (totype (.getType fld))]
(when getter
@@ -469,7 +469,7 @@
(let [{:keys [name bytecode]} (apply gen-class (str name) options)
file (java.io.File. path (str (. name replace \. (. java.io.File separatorChar)) ".class"))]
(.createNewFile file)
- (with-open f (java.io.FileOutputStream. file)
+ (with-open [f (java.io.FileOutputStream. file)]
(.write f bytecode))))
(comment
diff --git a/src/clj/clojure/proxy.clj b/src/clj/clojure/proxy.clj
index f72111a..2bf37b8 100644
--- a/src/clj/clojure/proxy.clj
+++ b/src/clj/clojure/proxy.clj
@@ -70,7 +70,7 @@
;if found
(. gen (loadThis))
;box args
- (dotimes i (count ptypes)
+ (dotimes [i (count ptypes)]
(. gen (loadArg i))
(. clojure.lang.Compiler$HostExpr (emitBoxReturn nil gen (nth pclasses i))))
;call fn
@@ -101,7 +101,7 @@
(. cv (visitField (+ (. Opcodes ACC_PRIVATE) (. Opcodes ACC_VOLATILE))
fmap (. map-type (getDescriptor)) nil nil))
;add ctors matching/calling super's
- (doseq #^Constructor ctor (. super (getDeclaredConstructors))
+ (doseq [#^Constructor ctor (. super (getDeclaredConstructors))]
(when-not (. Modifier (isPrivate (. ctor (getModifiers))))
(let [ptypes (to-types (. ctor (getParameterTypes)))
m (new Method "<init>" (. Type VOID_TYPE) ptypes)
@@ -165,7 +165,7 @@
(recur mm considered (. c (getSuperclass))))
mm))]
;add methods matching supers', if no mapping -> call super
- (doseq #^java.lang.reflect.Method meth (vals mm)
+ (doseq [#^java.lang.reflect.Method meth (vals mm)]
(gen-method meth
(fn [gen m]
(. gen (loadThis))
@@ -178,8 +178,8 @@
(. m (getDescriptor)))))))
;add methods matching interfaces', if no mapping -> throw
- (doseq #^Class iface interfaces
- (doseq #^java.lang.reflect.Method meth (. iface (getMethods))
+ (doseq [#^Class iface interfaces]
+ (doseq [#^java.lang.reflect.Method meth (. iface (getMethods))]
(when-not (contains? mm (method-sig meth))
(gen-method meth
(fn [gen m]
diff --git a/src/clj/clojure/xml/xml.clj b/src/clj/clojure/xml/xml.clj
index 516eb06..117016a 100644
--- a/src/clj/clojure/xml/xml.clj
+++ b/src/clj/clojure/xml/xml.clj
@@ -95,12 +95,12 @@
(do
(print (str "<" (name (:tag e))))
(when (:attrs e)
- (doseq attr (:attrs e)
+ (doseq [attr (:attrs e)]
(print (str " " (name (key attr)) "='" (val attr)"'"))))
(if (:content e)
(do
(println ">")
- (doseq c (:content e)
+ (doseq [c (:content e)]
(emit-element c))
(println (str "</" (name (:tag e)) ">")))
(println "/>")))))
