Menene ƴari-ƴariya (decorators) kuma ta zā yi aiki ta rubuta daya?

Question

Accepted Answer

**Ƴari-ƴari** aiki ce wacce **ke naɗa wata aiki** domin ƙara hali, ba tare da canji code na asali ba. Ake shafa shi tare da `@decorator` suntax sama da aiki — hanya clean don ƙara alaƙa da ɗaka gida kamar bayyani, lokaci, tajewa, ko shawo.

## Yadda ƴari-ƴariya ke aiki

```python
def my_decorator(func):
    def wrapper(*args, **kwargs):       # wraps the original function
        print("before")
        result = func(*args, **kwargs)  # call the original
        print("after")
        return result
    return wrapper                       # return the wrapped version

@my_decorator
def greet(name):
    print(f"Hello {name}")

greet("Ann")
# Output: before / Hello Ann / after
```

`@my_decorator` suntax shi ne gida don `greet = my_decorator(greet)` — shi na canja `greet` tare da `wrapper`, wanda ke gudana code ƙarin kewaye ga gayyace na asali. `*args, **kwargs` yana sa wrapper ya aiki ga kowane sigine aiki.

## Misali na aiki: lokaci

```python
import time, functools

def timed(func):
    @functools.wraps(func)        # preserves func's name/docstring (important!)
    def wrapper(*args, **kwargs):
        start = time.perf_counter()
        result = func(*args, **kwargs)
        print(f"{func.__name__} took {time.perf_counter() - start:.3f}s")
        return result
    return wrapper

@timed
def slow_task():
    time.sleep(1)
```

`@functools.wraps(func)` mahimmaci ne — ba tare da shi, aiki na lullucci yana rasa sunansa da docstring na asali.

## Ƴari-ƴariya tare da jajjagade

```python
def repeat(times):               # outer takes the decorator's argument
    def decorator(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            for _ in range(times):
                func(*args, **kwargs)
        return wrapper
    return decorator

@repeat(times=3)
def hello(): print("hi")  # prints "hi" three times
```

A parameter ƴari-ƴari yana buƙatar matakin ƙari (aiki da ke dawowa ƴari-ƴari).

## Gargajiya ƴari-ƴariya tare da / gida

```text
@property            → turn a method into a computed attribute
@staticmethod / @classmethod → method types
@functools.lru_cache → memoize results
@app.route("/")      → web framework routing (Flask)
@pytest.fixture      → test fixtures
```

## Me yake damun wannan

ƴari-ƴariya aiki ce mai ƙarfi, wanda ke taɓawa Python don **ƙara hali mai sake amfani** (bayyani, lokaci, tajewa, tabbacewa, bincike, hanya) zuwa aiki cikin gida da fassarwa — rabuwa da alaƙa da ɗaka gida daga aiki na asali.

Su ke nan gida a cikin Python na gaske: frameworks na gida (`@app.route`), tajewa (`@lru_cache`), ajiya (`@property`), da bincike.

Sanin yadda za a rubuta su (aiki na lullucci, `*args/**kwargs`, `functools.wraps`) da sifa na parameter yana bata ability don fayowa tare da ƴari-ƴariya na ecosystem cikin daidai-daidai kuma gina sauran kai-kai rashin karoshi.