Add support of recursive loops about jinjava

[zaycev]

Or possibly, there is some other way to traverse tree structures with arbitrary depth?

[boulter]

Hi @zaycev. You can have nested for loops. Theoretically you could define a macro to iterate over a tree, but we prevent macros from calling themselves because it's too easy to create a cycle.

Jinjava do not yet support the recursive option on for loops, but it may not be something we want to do for the reasons mentioned above.

[joncfoo]

In case someone comes across this issue & is looking for a workaround... in our project we ended up duplicating the macros and ping-ponging between them to achieve the recursive effect.

May Knuth forgive us >_>

[TheWebTech]

Pinging that I would like this to be possible, or at least recursive Macros to be possible.

I tried implementing a nav using recursive macros, it appeared the server was saying "naw man, you're going down a slippery slope toward allowing infinite loops"

[jboulter]

We're pretty explicitly not allowing this. It's too easy to recurse infinitely. #54

[TheWebTech]

I completely understand the reasoning, just puts devs into a bind of repeating a lot of code, resulting in it being more error prone etc.

Would a happy compromise be to only allow recursing x levels deep?

For example a use case I have is generating a custom menu structure(very similar to original poster)
Most of the HTML is nearly identical that I'm generating.

For a menu the maximum I could ever see someone doing this is ~9 levels deep(thinking extra wacky mega menu)

For most situations 2-3 levels of recursion would be just fine.

This would make templating easier, as we could use recursion, but would prevent inexperienced devs from taking down whole servers.