4 ms·

Not to mention that expressions after the case keyword have completely different semantics from expressions ANYWHERE else. a | b is not the bitwise or of a with

• vitus 6y ago
  You can already define __or__ to do whatever you want! This is already special-cased in the standard library for, say, set union (where admittedly the concept is more similar to bitwise or).
  • toxik 6y ago
    ... except in case expressions Thanks for proving my point though!
• amirkdv 6y ago
  This part is truly strange. This example from the tutorial drove it home for me: match event.get(): case Click(position=(x, y)): handle_click_at(x, y) case KeyPress(key_name="Q") | Quit(): game.quit() where `Click(position=(x, y))` is not at all what one would expect. What I still don't understand is: does the new syntax magically do this to a user-defined class? i.e. if I say foo = Click(position=(x, y)) vs ... case Click(position=(x, y)) those identical expressions, for the same value of Click, have widely different semantics? edit: typo fix
  • bobbylarrybobby 6y ago
    You are (sadly) correct. The latter example checks that the type of `event.get()` is a Click, then that it has a `.position` attribute that be restructured into a two-element tuple `(x,y)`. It's equivalent to `ev = event.get(); if isinstance(ev, Click): (x,y) = ev.position`