echo/src/echo/iteration_helpers.py at master · cdleary/echo

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from typing import Any, Callable

from echo.interp_result import Result

from echo.eobjects import get_guest_builtin

from echo.interp_context import ICtx

def foreach(iterable: Any, callback: Callable[[Any], Result[bool]],

ictx: ICtx) -> Result[None]:

do_iter = get_guest_builtin('iter')

do_next = get_guest_builtin('next')

it = do_iter.invoke((iterable,), {}, {}, ictx)

if it.is_exception():

return Result(it.get_exception())

it = it.get_value()

while True:

item = do_next.invoke((it,), {}, {}, ictx)

if (item.is_exception() and isinstance(

item.get_exception().exception, StopIteration)):

break

if item.is_exception():

return Result(item.get_exception())

cb_res = callback(item.get_value())

if cb_res.is_exception():

return Result(cb_res.get_exception())

keep_going = cb_res.get_value()

assert isinstance(keep_going, bool), keep_going

if not keep_going:

break

return Result(None)