"""Create a list of components from an iterable.""" from __future__ import annotations from typing import Any, Callable, List from pynecone.components.component import Component from pynecone.components.layout.fragment import Fragment from pynecone.components.tags import IterTag from pynecone.vars import BaseVar, Var, get_unique_variable_name class Foreach(Component): """A component that takes in an iterable and a render function and renders a list of components.""" # The iterable to create components from. iterable: Var[List] # A function from the render args to the component. render_fn: Callable = Fragment.create @classmethod def create(cls, iterable: Var[List], render_fn: Callable, **props) -> Foreach: """Create a foreach component. Args: iterable: The iterable to create components from. render_fn: A function from the render args to the component. **props: The attributes to pass to each child component. Returns: The foreach component. Raises: TypeError: If the iterable is of type Any. """ try: type_ = iterable.type_.__args__[0] except Exception: type_ = Any iterable = Var.create(iterable) # type: ignore if iterable.type_ == Any: raise TypeError( f"Could not foreach over var of type Any. (If you are trying to foreach over a state var, add a type annotation to the var.)" ) arg = BaseVar(name="_", type_=type_, is_local=True) return cls( iterable=iterable, render_fn=render_fn, children=[IterTag.render_component(render_fn, arg=arg)], **props, ) def _render(self) -> IterTag: return IterTag(iterable=self.iterable, render_fn=self.render_fn) def render(self): """Render the component. Returns: The dictionary for template of component. """ tag = self._render() try: type_ = self.iterable.type_.__args__[0] except Exception: type_ = Any arg = BaseVar( name=get_unique_variable_name(), type_=type_, ) index_arg = tag.get_index_var_arg() component = tag.render_component(self.render_fn, arg) return dict( tag.add_props( **self.event_triggers, key=self.key, sx=self.style, id=self.id, class_name=self.class_name, ).set( children=[component.render()], props=tag.format_props(), ), iterable_state=tag.iterable.full_name, arg_name=arg.name, arg_index=index_arg, )