Question on node.parse

[leojplin]

Hi, as I am starting to learn to use this library. I have some questions. I was trying out the examples, and I found out that in order to traverse the children of a node, I first have to manually call parse on the node first. This doesn't seem very ergonomic, is there a reasoning behind this, and could that be changed? Also, why do we pass in the parent object when calling parse? From the same example, it is passing itself as the parent to the parse method, which seems kinda unintuitive.

[spd789562]

So, first thing is Arc<RwLock<WzNode>> is a basic unit, I need the Arc for parent referencing and RwLock for inner mutability like Rc<RefCell<T>> in single thread context.

Parse a WzFile or WzImage means something like unzip it, and since it might be pretty giant (like Map.wz in old version will like 2G), it's not good to be parsed in the first place. so I'm will not going to change it and it not hard to create a wrap around it.

And for parsing need to reference self, it's also for the parent referencing reason. You see, when we parsing the WzImage, and read out first node WzSubProperty::Property, how do we let the node know it is WzImage ? and yes we need a Weak<RwLock<WzNode>> for safe reference, which is mean we need an &Arc<RwLock<WzNode>> of WzImage it self and downgrade it and assign to WzSubProperty::Property.
It not easy task, this library provides a parse_node to save some boilerplate, I've tried to create a Trait for Arc<RwLock<WzNode>> before, and I found out implicitly run a function on Arc<RwLock<T>> is pretty bad thing, since we don't know what it will do inside and probably causing dead lock (and yes, I'm do ), let library provide it also bad thing. That's what I think of.

all thing start from Arc<RwLock<WzNode>> and along with weirdness and unfriendly interface. I'm still not sure what a workaround is, other than using GC system or just changing to a language that uses GC :/

[leojplin]

Thanks for the explanation! I don't know rust too well right now, as coming from a GC language, let me keep playing with it :)

[spd789562]

ye, good luck. I'm also not learn really well when I create this project, but I learn a lot along the way! It's pretty hard to solve the referencing-related problem of Rust.

[leojplin]

btw, i just realize we have the exact same english name!!! 😂