not-lazy-eval.py

from dataclasses import dataclass

@dataclass
class Stop:
    value: any

@dataclass
class Resume:
    value: any

def runWith(generator, handlers: list[callable]):
    yield_result = None
    
    while True:
        try:
            yielded = generator.send(yield_result)
            
            for h in handlers:
                r = h(yielded)
                if r is None:
                    continue
                if isinstance(r, Resume):
                    yielded = r
                elif isinstance(r, Stop):
                    return r
            else:
                yielded = None
            
        except StopIteration as s:
            return s.value

def fib():
    a, b = 0, 1
    while True:
        yield a
        a, b = b, a + b

def genFibs(limit: int) -> list[int]:
    count = 0
    fibs = []
    
    def handler(i):
        nonlocal count, fibs
        
        if not isinstance(i, int):
            return None
            
        if count < limit:
            count += 1
            fibs.append(i)
            return Resume(None)
            
        return Stop(None)
        
    
    runWith(fib(), [handler])
    return fibs
    
print(genFibs(10))