# 危險！這是一個典型的無限循環(huán)
count = 0
while count < 10:
    print("Hello, World!")  # 缺少count遞增語句

import signal

running = True

def shutdown(signum, frame):
    global running
    print("\nShutting down gracefully...")
    running = False

signal.signal(signal.SIGINT, shutdown)  # 注冊Ctrl+C處理

while running:
    # 處理請求的代碼
    pass

# 錯誤示例：計數(shù)器未遞增
total = 0
i = 1
while i <= 100:
    total += i
    # 嚴重遺漏：缺少 i += 1
print(f"1到100的和為: {total}")  # 永遠不會執(zhí)行到這行！

total = 0
i = 1
while i <= 100:
    total += i
    i += 1  # ? 關(guān)鍵修復(fù)：遞增計數(shù)器
print(f"1到100的和為: {total}")  # 輸出: 5050

# 錯誤示例：錯誤的終止條件
num = 10
while num != 0:  # 問題：num每次減2，會跳過0
    print(num)
    num -= 2

num = 9
while num > 0:  # ? 用 > 0 替代 != 0
    print(num)
    num -= 2
# 輸出: 9,7,5,3,1 后正常終止

# 錯誤示例：用浮點數(shù)作為循環(huán)條件
x = 0.0
while x != 1.0:
    print(x)
    x += 0.1

0.0
0.1
0.2
0.30000000000000004
0.4
0.5
0.6
0.7
0.7999999999999999
0.8999999999999999
0.9999999999999999
1.0999999999999999  # 跳過1.0，x > 1.0 永不滿足 != 1.0
...無限循環(huán)

x = 0.0
while x < 1.0:  # ? 用 < 替代 !=
    print(x)
    x += 0.1

import math

x = 0.0
while not math.isclose(x, 1.0, abs_tol=1e-9):
    print(x)
    x += 0.1

# 錯誤示例：嵌套循環(huán)變量沖突
for i in range(5):
    print(f"外層循環(huán) i={i}")
    j = 0
    while j < 3:
        print(f"  內(nèi)層循環(huán) j={j}")
        # 嚴重錯誤：意外修改了外層變量
        i += 1  # ? 錯誤地修改了外層i
        j += 1

for i in range(5):
    print(f"外層循環(huán) i={i}")
    for j in range(3):  # ? 用for替代while，避免手動管理j
        print(f"  內(nèi)層循環(huán) j={j}")
    # 無需額外操作，j的作用域僅限內(nèi)層

# 錯誤示例：假設(shè)用戶總會輸入有效數(shù)據(jù)
while True:
    user_input = input("請輸入一個正整數(shù)（輸入0退出）: ")
    num = int(user_input)
    if num == 0:
        break
    print(f"你輸入的數(shù)字是: {num}")

# 隱蔽的無限循環(huán)風(fēng)險
response = ""
while response != "yes":
    response = input("繼續(xù)嗎？(yes/no): ").lower()
    # 如果用戶輸入"y"或"YES"，循環(huán)永不終止！

while True:
    user_input = input("請輸入一個正整數(shù)（輸入0退出）: ").strip()
    if user_input == "0":
        break
    try:
        num = int(user_input)
        if num > 0:
            print(f"有效輸入: {num}")
        else:
            print("?? 請輸入正整數(shù)！")
    except ValueError:
        print("? 無效輸入！請重新輸入數(shù)字。")

# 錯誤示例：斐波那契數(shù)列的無限遞歸
def fibonacci(n):
    # 缺少基線條件：未定義n=0或n=1時的返回值
    return fibonacci(n-1) + fibonacci(n-2)

print(fibonacci(5))  # 立即觸發(fā) RecursionError

def fibonacci(n):
    if n == 0:  # ? 基線條件1
        return 0
    elif n == 1:  # ? 基線條件2
        return 1
    else:
        return fibonacci(n-1) + fibonacci(n-2)

MAX_ITERATIONS = 1000
count = 0
total = 0

while count < 100:  # 主條件
    total += count
    count += 1
    
    # 安全閥：防止邏輯錯誤導(dǎo)致無限循環(huán)
    if count > MAX_ITERATIONS:
        raise RuntimeError("?? 循環(huán)超過最大迭代次數(shù)！檢查邏輯錯誤")

count = 0
while count < 100:
    assert count >= 0, "計數(shù)器不應(yīng)為負數(shù)！"  # 條件不滿足時拋出AssertionError
    # 循環(huán)體代碼...
    count += 1

count = 0
while count < 10:
    print(f"DEBUG: count={count}, condition={count < 10}")  # 監(jiān)控狀態(tài)
    # 循環(huán)體代碼...
    count += 0.5  # 假設(shè)此處有錯誤（如+=0.4）

DEBUG: count=0, condition=True
DEBUG: count=0.5, condition=True
...
DEBUG: count=9.5, condition=True
DEBUG: count=10.0, condition=False  # 正常終止

import sys

def trace_calls(frame, event, arg):
    if event == 'line':
        # 每執(zhí)行一行代碼觸發(fā)
        if "count" in frame.f_locals:
            print(f".debugLine: count={frame.f_locals['count']}")
    return trace_calls

sys.settrace(trace_calls)

count = 0
while count < 5:
    count += 1  # 觀察count變化

sys.settrace(None)  # 關(guān)閉追蹤

# 安裝工具
pip install pylint

# 分析文件
pylint my_script.py

my_script.py:5:8: W0603 (using-constant-test) 
  Using constant test in while loop (always true)

i = 0
while i < len(data):
    process(data[i])
    i += 1  # 可能遺漏或錯誤修改

for item in data:  # ? 自動遍歷所有元素
    process(item)

# 安全獲取索引
for index, value in enumerate(data):
    if value > threshold:
        print(f"在位置{index}發(fā)現(xiàn)異常值")

import time

orders = []  # 模擬訂單隊列

def check_new_orders():
    """持續(xù)檢查新訂單（問題版本）"""
    while True:
        if new_orders := get_new_orders():  # 假設(shè)此函數(shù)獲取新訂單
            process_orders(new_orders)
        else:
            time.sleep(1)  # 無訂單時休眠1秒

def get_new_orders():
    # 模擬：50%概率返回訂單
    import random
    return ["Order1", "Order2"] if random.random() > 0.5 else []

def process_orders(orders):
    print(f"處理 {len(orders)} 個新訂單")

# 啟動監(jiān)控
check_new_orders()

def get_new_orders():
    raise ConnectionError("數(shù)據(jù)庫連接失敗")  # 模擬故障

# 生產(chǎn)環(huán)境實際代碼（簡化）
while True:
    try:
        check_new_orders()  # 此函數(shù)崩潰后，外層循環(huán)立即重啟它
    except Exception as e:
        log_error(e)
        time.sleep(0.1)  # 休眠很短，快速重試

MAX_RETRIES = 5  # 最大重試次數(shù)

def check_new_orders():
    retry_count = 0
    while True:
        try:
            if new_orders := get_new_orders():
                process_orders(new_orders)
                retry_count = 0  # 成功后重置計數(shù)器
            else:
                time.sleep(1)
        except Exception as e:
            retry_count += 1
            print(f"?? 獲取訂單失敗 (嘗試 {retry_count}/{MAX_RETRIES}): {str(e)}")
            
            # 安全退出：超過重試次數(shù)
            if retry_count >= MAX_RETRIES:
                raise RuntimeError("訂單服務(wù)持續(xù)故障，停止重試") from e
            
            time.sleep(2 ** retry_count)  # 指數(shù)退避

def check_new_orders():
    # ... [同上]
        except Exception as e:
            # 添加詳細日志
            import logging
            logging.error(f"訂單檢查失敗 ID:{id(e)}", exc_info=True)
            # ... [其余邏輯]

def monitor_orders():
    """主監(jiān)控函數(shù)（頂層安全循環(huán)）"""
    while True:
        try:
            check_new_orders_once()  # 單次檢查，有明確退出
        except CriticalError:
            break  # 僅當(dāng)嚴重錯誤時退出
        except Exception as e:
            handle_transient_error(e)  # 處理臨時故障
        time.sleep(0.5)  # 統(tǒng)一休眠點

def check_new_orders_once():
    """單次訂單檢查（無循環(huán)）"""
    if new_orders := get_new_orders():
        process_orders(new_orders)

import asyncio

async def main():
    print("服務(wù)啟動...")
    # 業(yè)務(wù)邏輯（可包含await）
    while True:
        await asyncio.sleep(1)
        print("心跳")

# 安全啟動事件循環(huán)
try:
    asyncio.run(main())
except KeyboardInterrupt:
    print("\n收到退出信號，正在清理...")
    # 執(zhí)行清理操作
    print("服務(wù)已安全停止")

import time

start_time = time.time()
TIMEOUT = 3600  # 1小時超時

while True:
    # 檢查是否超時
    if time.time() - start_time > TIMEOUT:
        print("?? 循環(huán)達到最大運行時間，安全退出")
        break
    
    # 業(yè)務(wù)邏輯
    process_data()
    
    # 避免CPU空轉(zhuǎn)
    time.sleep(0.1)

import threading
import time

class OrderMonitor:
    def __init__(self):
        self.running = True
    
    def start(self):
        threading.Thread(target=self._monitor_loop, daemon=True).start()
    
    def stop(self):
        self.running = False  # 安全信號
    
    def _monitor_loop(self):
        while self.running:
            try:
                # 檢查訂單邏輯
                time.sleep(1)
            except Exception as e:
                print(f"監(jiān)控錯誤: {e}")

# 使用示例
monitor = OrderMonitor()
monitor.start()

try:
    input("按Enter停止服務(wù)...\n")
finally:
    monitor.stop()  # 安全終止