Python's inline if's still read backwards to me and it would be nice to switch the order. But we are kind of stuck with it. I also don't want to introduce new control structures in this lib. Just want to use whatever Python has to offer in terms of control structures/syntax to make it more approachable.

htpy supports generators/callables as children (https://htpy.dev/streaming/). As long as you are careful to wrap things in generators/lambdas everything is lazy. Implementing if_ and for_ is straightforward and anyone can build constructs like that to use. But will not be lazy unless all arguments are wrapped in lambdas:

  from htpy import div, li, ul

  def if_(cond, a, b):
      return a() if cond() else b()

  def for_(items, func):
      return (func(item) for item in items())

  print(div[if_(lambda: True, lambda: "True!", lambda: "False!")])
  print(div[if_(lambda: False, lambda: "True!", lambda: "False!")])
  print(ul[for_(lambda: ["a", "b", "c"], lambda x: li[x])])

output:

  <div>True!</div>
  <div>False!</div>
  <ul><li>a</li><li>b</li><li>c</li></ul>