# this file available at: https://arachnoid.com/files/python01/
import math
from typing import List

def student_error_00():
    print(f'\tLoop numeric float test: detect zero.')
    n = 0.3
    while n >= -0.31:
        print(f'\tn = {n:18.15f} or {n:22.15e}, equals zero? {n == 0.0}')
        # test for zero
        if n == 0.0:
            break
        else:
            n -= .1

def student_error_01_append_test(mylist :List[str] = []):
    # a function default value is only applied
    # once, when the function is defined, not
    # each time the function is called.
    mylist.append(f"append {len(mylist)}")
    print(f'\t{mylist}')

def student_error_01():
    print('\tAppend to empty list:')
    for _ in range(5):
        student_error_01_append_test()

def student_error_02():
    try:
        _ = math.log(0)
    except Exception as e:
        print(f'\tCaught error = {e}')
    print('\t... function continues from here.')

def student_error_03():
    try:
        x = math.log(0)
        print(f'\tx = {x}')
    except Exception as err:
        print(f'\tCaught outer error: {err}')
        try:
            y = 1/0
            print(f'\tx = {y}')
        except Exception as err:
            print(f'\tCaught inner error: {err}')
    print('\t... function continues from here.')



examples = (
    student_error_00,
    student_error_01,
    student_error_02,
    student_error_03,
)

def main():
    for example in examples:
        print(f'Running {example.__name__}:')
        example()
        print() 

if __name__ == "__main__":
    main()