from typing import Any
from core.primitives.list import cons, car, cdr, NIL
from core.exceptions import syntaxError
from core.printer import Representation

def getFirstN(_list: Any, n: int) -> list[Any]:
    """Get first N elements.

    Args:
        _list: A list.
        n: The expected number of elements.

    Returns:
        A list of the extracted elements.

    Raises:
        syntaxError: If the list has wrong number of elements.
    """
    result: list[Any] = []
    current: Any = _list

    while current != NIL and len(result) < n:
        result.append(car(current))
        current = cdr(current)
    
    if current != NIL:
        raise syntaxError(f"extra elems: {Representation(current)}")
    
    if len(result) < n:
        raise syntaxError("lack of elems")
    
    return result