Clojure Q&A - Recent questions in tools.trace

Can the clojure.tools.trace reflection warnings be addressed?

Thu, 11 Feb 2021 18:39:41 +0000

I frequently see these as part of my daily workflow - which is slightly inconvenient:

Reflection warning, clojure/tools/trace.clj:231:54 - call to method setStackTrace on java.lang.Object can't be resolved (no such method).
Reflection warning, clojure/tools/trace.clj:242:56 - call to method setStackTrace on java.lang.Object can't be resolved (no such method).
Reflection warning, clojure/tools/trace.clj:244:49 - call to java.lang.Exception ctor can't be resolved.
Reflection warning, clojure/tools/trace.clj:244:69 - call to method setStackTrace on java.lang.Object can't be resolved (no such method).
Reflection warning, clojure/tools/trace.clj:256:56 - call to method setStackTrace on java.lang.Object can't be resolved (no such method).
Reflection warning, clojure/tools/trace.clj:259:49 - call to java.lang.Throwable ctor can't be resolved.
Reflection warning, clojure/tools/trace.clj:259:69 - call to method setStackTrace on java.lang.Object can't be resolved (no such method).
Reflection warning, clojure/tools/trace.clj:275:56 - call to method setStackTrace on java.lang.Object can't be resolved (no such method).
Reflection warning, clojure/tools/trace.clj:276:68 - call to method setStackTrace on java.lang.Object can't be resolved (no such method).

Checking out the tools.trace code @ master, these seem tractable.

Could these reflection warnings be avoided?

Small correction to example use in README - trace-ns requires quoted symbol in latest release 0.7.9

Sat, 08 Sep 2018 14:21:31 +0000

While there are unreleased changes to tools.trace to enable a form like this to work:

(trace-ns myown.namespace)

the latest released version of tools.trace is 0.7.9, and in that version the above causes an exception to be thrown. It works if you quote the symbol, like so:

(trace-ns 'myown.namespace)

Document how to trace non-public fns

Wed, 22 Nov 2017 20:41:25 +0000

Add an example of how to trace a non-public fn by passing it as a var.

Especially as a Clojure beginner, this might a very helpful information.

Add throttling/rate-limiting

Sun, 01 Feb 2015 11:57:30 +0000

I would like to propose adding several features to tools.trace:

The ability to trottle tracing using several characteristics:
```
 *  Number of messages logged.
```
- Number of times called.
- Size of output generated
- Times logged in a given period
The ability to trace only certain calls:
* Trace calls to functions with specific values for their argument

Use aprint when displaying value

Wed, 29 Oct 2014 16:09:15 +0000

Problem: when trace-ns is used, very long displays in the output stream is very hard to read when the fn calls are important and with voluminous data structure
Solution: Use (link: https://github.com/razum2um/aprint text: Aprint library) when printing value in the output string, now get syntax hightlighting and better layout of data structure
Tradeoffs: add a new dependency to tools.trace
Tests: yes, modify the cleanup fn to also clean the color information added by aprint, so 100% tests passed