[Ur] Ur/Web in production

Sergey grrwlf at gmail.com
Sat Jan 18 02:58:17 EST 2014

Vladimir, thanks for the review! Here are my 2 cents:

On 17.01.2014 00:30, Vladimir Shabanov wrote:
> Compiler bugs. As you can expect from a new and complex tool there were
> several bugs in compiler and runtime library. Most of them are in the past
> now. However I'm still not sure about one nasty bug when some effectful
> computation were optimized out (click on button and part of event handler
> is not executed at all, whoops). It's the most annoying bug I've met in
> Ur/Web. Usually solved by some code reordering or by calling it via
> JavaScript FFI function (look for 'forceImpure' in the sources). Hope it's
> fixed since I haven't seen it for a while.

Looks like I have an example of such bug. I've noticed that one test for 
urweb-monad-pack library doesn't execute all the client-side handlers:


The program should popup two alerts at startup but for some reason only 
the last one appears.


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