Clojure Q&A - Recent questions tagged 1.12

Clojure 1.12 breaks Serialization for records implementing IFn

Fri, 21 Feb 2025 20:51:39 +0000

If you have a class/record that implements a functional interface AND IFn, serializing it will throw the same error as CLJ-2880. Here's a repro

(let [^java.util.function.Function my-f
      (reify
        Serializable
        java.util.function.Function
        clojure.lang.IFn
        )]
  (with-open [os (java.io.ObjectOutputStream. (java.io.ByteArrayOutputStream.))]
    (.writeObject os my-f)))

Will throw java.io.NotSerializableException. If you comment out clojure.lang.IFn, this code works.

This is a regression from 1.11.

Java interop issue

Tue, 12 Nov 2024 19:25:31 +0000

Hi everyone,

Failing to make clojure work with our commercial java library. I can run the following Java code on my machine and it works fine:

import com.numerix.pro.Application;
import com.numerix.pro.ApplicationCall;
import com.numerix.pro.ApplicationData;
import com.numerix.pro.ApplicationObjectFactory;
import com.numerix.pro.ApplicationWarning;

public final class FxAmericanOption {

    public static void main(final String argv[]) 
    {
        int rVal = 0;      // exit value
        try {
            System.out.println("Running: " + new Throwable().getStackTrace()[0].getClassName() + "\n");

            final Application app = new Application();
            {
                final ApplicationCall call = new ApplicationCall();
                call.addValue("ID",       "USD_Curve");
                call.addValue("OBJECT",   "Curve");
                call.addValue("TYPE",     "Yield");
                call.addValue("Now Date", ApplicationObjectFactory.parseDate("26-Oct-2003"));
                call.addValue("CURRENCY", "USD");
                call.addValue("RATE",     0.04);

                final String[] outHeaders =
                    new String[] {"Updated", "Timer", "ID"};

                final ApplicationWarning warning = new ApplicationWarning();

                app.call(call, outHeaders, warning);

I tried porting it to clojure 1.12 like this

(ns hello
  (:import (com.numerix.pro Application ApplicationCall
                            ApplicationWarning 
                            ApplicationObjectFactory)))
           
(def myapp (new Application))
(def appcall (new ApplicationCall))
(def warning (new ApplicationWarning))

(.addValue ^ApplicationCall appcall "NAME" "Yield Curve")
(.addValue ^ApplicationCall appcall "ID" "MyCurve")
(.addValue ^ApplicationCall appcall "OBJECT" "Curve")
(.addValue ^ApplicationCall appcall "TYPE" "Yield")
(.addValue ^ApplicationCall appcall "Now Date" (ApplicationObjectFactory/parseDate "26-Oct-2023"))
(.addValue ^ApplicationCall appcall "CURRENCY" "USD")
(.addValue ^ApplicationCall appcall "RATE" 0.04)

(def outHeaders (into-array String ["timer" "id"]))

(^[ApplicationCall String/1 ApplicationWarning] Application/.call ^Application myapp
                                                                  ^ApplicationCall appcall
                                                                  ^String/1 outHeaders
                                                                  ^ApplicationWarning warning)

I can inspect appcall object and it looks totally fine - all the .addValue register correctly with it. But when I evaluate the last form with Application/.call I get an error which I don't understand how to address..

 Execution error (IllegalAccessError) at hello/eval10370 (REPL:25).
; failed to access class com.numerix.pro.ApplicationCommon from class hello$eval10370 (com.numerix.pro.ApplicationCommon is in unnamed module of loader 'app'; hello$eval10370 is in unnamed module of loader clojure.lang.DynamicClassLoader @cc01572)

Any help much appreciated!

New add-lib in Clojure 1.12 doesn't load data readers brought by the lib

Tue, 20 Aug 2024 20:42:06 +0000

I see that the new add-lib in Clojure 1.12 doesn't call clojure.core/load-data-readers (like clojure.core does on loading) so if you bring libraries that have data-readers you can't use them.

Calling clojure.core/load-data-readers from the repl doesn't solve the issue since it changes *data-readers* root value which is already being shadowed by clojure.main/repl.

$ clj -Sdeps '{:deps {org.clojure/clojure {:mvn/version "1.12.0-rc1"} com.github.flow-storm/flow-storm-dbg {:mvn/version "3.17.2"}}}'
Clojure 1.12.0-rc1
user=> *data-readers*
{trace #'flow-storm.api/read-trace-tag, ctrace #'flow-storm.api/read-ctrace-tag, rtrace #'flow-storm.api/read-rtrace-tag, tap #'flow-storm.api/read-tap-tag, tap-stack-trace #'flow-storm.api/read-tap-stack-trace-tag, flow-storm.types/value-ref #'flow-storm.types/make-value-ref, amalloy/ring-buffer #'amalloy.ring-buffer/read-method}

now with add-lib :

$ clj -Sdeps '{:deps {org.clojure/clojure {:mvn/version "1.12.0-rc1"}}}'                                                             
Clojure 1.12.0-rc1
user=> (add-lib 'com.github.flow-storm/flow-storm-dbg {:mvn/version "3.17.2"})
[...]
user=> *data-readers*
{}
user=> (#'clojure.core/load-data-readers)
{trace #'flow-storm.api/read-trace-tag, ctrace #'flow-storm.api/read-ctrace-tag, rtrace #'flow-storm.api/read-rtrace-tag, tap #'flow-storm.api/read-tap-tag, tap-stack-trace #'flow-storm.api/read-tap-stack-trace-tag, flow-storm.types/value-ref #'flow-storm.types/make-value-ref, amalloy/ring-buffer #'amalloy.ring-buffer/read-method}
user=> *data-readers*
{}

The only way I see to bring in data-readers with add-lib is by starting a sub-repl :

clj -Sdeps '{:deps {org.clojure/clojure {:mvn/version "1.12.0-rc1"}}}'
Clojure 1.12.0-rc1
user=> (add-lib 'com.github.flow-storm/flow-storm-dbg {:mvn/version "3.17.2"})
[...]
user=> (binding [*data-readers* (#'clojure.core/load-data-readers)] (clojure.main/repl))
user=> *data-readers*
{trace #'flow-storm.api/read-trace-tag, ctrace #'flow-storm.api/read-ctrace-tag, rtrace #'flow-storm.api/read-rtrace-tag, tap #'flow-storm.api/read-tap-tag, tap-stack-trace #'flow-storm.api/read-tap-stack-trace-tag, flow-storm.types/value-ref #'flow-storm.types/make-value-ref, amalloy/ring-buffer #'amalloy.ring-buffer/read-method}

which won't work with nrepl tooling.

Make partitionv faster

Wed, 30 Aug 2023 16:34:12 +0000

If we use the cat transducer instead of calling (concat p pad), the code is much faster:

(defn partitionv [n step pad coll]
  (lazy-seq
    (when-let [s (seq coll)]
      (let [p (into [] (take n) s)]
        (if (= n (count p))
          (cons p (partitionv n step pad (nthrest s step)))
          (list (into [] (take n) (concat p pad))))))))

can be changed to

(defn partitionv2 [n step pad coll]
  (lazy-seq
    (when-let [s (seq coll)]
      (let [p (into [] (take n) s)]
        (if (= n (count p))
          (cons p (partitionv n step pad (nthrest s step)))
          (list (into [] (comp cat (take n)) [p pad])))))))