IDOM – It's React, but in Python • Hacker News Board

Re: IDOM – It's React, but in Python

#11

Post by jackhalford » Sat, Feb 20, 2021, 7:33 PM UTC

wodenokoto wrote: post #10

As a Python dev this code is extremely difficult to follow. If I take off my Python glasses it kinda makes sense reading the examples. Take a look at ‘toggle_1()’ function, which is called by a lambda, and takes no arguments. On top of that, it refers to ‘toggle_state()’ which also doesn’t take any arguments. That function calls ‘set_state()’ and is fed a lambda which toggles a Boolean input and somehow all that swit…

> I get that this code generates a JavaScript/html application which will eventually get executed and therefore everything happens one extra step detached from the Python code.

Are you sure? it seems every events goes to the server, which is a huge cost compared to fully client side event handling.

Re: IDOM – It's React, but in Python

#12

Post by frollo » Sat, Feb 20, 2021, 11:18 PM UTC

BossingAround wrote: post #4

Apologies, but why?

Exactly. One React is bad enough, why do we need even more versions of it?

Re: IDOM – It's React, but in Python

#13

Post by curryst » Sun, Feb 21, 2021, 12:40 AM UTC

wodenokoto wrote: post #10

As a Python dev this code is extremely difficult to follow. If I take off my Python glasses it kinda makes sense reading the examples. Take a look at ‘toggle_1()’ function, which is called by a lambda, and takes no arguments. On top of that, it refers to ‘toggle_state()’ which also doesn’t take any arguments. That function calls ‘set_state()’ and is fed a lambda which toggles a Boolean input and somehow all that swit…

It's weird, but count is basically a singleton here, where the state is shared with the thing that actually renders this.

> Wouldn’t everything be a lot less magical if it was oop? Then you’d go ‘input_1.toggle_state’ and it is pretty clear to everyone which variable is being toggled.

I think that's mostly mirroring the syntax from React (where things used to be classes, although functional React is getting more popular).

The main advantage of this singleton based approach is that the dataflow is unidirectional. It doesn't show up in their simple examples, but in more complicated ones, those variables get passed to child components. If you do OOP, you're passing a mutable object to the child component. With this approach, they get a read-only copy of the variable. You can overwrite the value, but it won't propagate up to the parents, so the component can only screw up itself.

It's different, but I don't think particularly magical. The magic is basically "for each component, see what singletons were passed to children. If any of the children's singletons changed, re-render the affected children". I'm not a React expert by any means, but once I got used to that functional paradigm, it doesn't bother me.