Conditional execution of custom async tags

[fabien]

Because the captured output will always be parsed and executed, it is currently impossible to implement a scenario where the async will only execute when required. Take for example a {% cache %} tag that would contain & capture async tags like {% fetch %}. It's currently impossible to return cached content, without already running fetch, and thus, defeating the purpose.

[jlongster]

I don't understand what you mean exactly, are tags running inside if blocks when they shouldn't?

I see no reason why fetch could not look into the cache created by a cache tag.

[fabien]

Yes, IIRC async tags will always execute, even when the parent block shouldn't run. It'd be interesting to see how the scenario above would best be implemented:

{% cache %}
<h1>{{ datestamp() }}</h1>
{% fetch 123 %} // async
{% endfetch %}
{% endcache %}

[jlongster]

Ah, I can't remember how async tags are transformed, I'll take a look at it soon