X'inhu lambdas u tools funzjonali map/filter/reduce?

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Accepted Answer

**lambda** huwa funzjoni żgħira, bla isem, ta' espressjoni waħda. **`map`**, **`filter`**, u **`reduce`** huma tools funzjonali li japplikaw funzjoni fuq kull element iterable. Flimkien jippermettu stil funzjonali — għalkemm Python ħafna drabi jippreferi comprehensions għat-tasks l-istess.

## Lambda — funzjoniet bla isem inline

```python
# a lambda is a one-line function with no name
square = lambda x: x ** 2
square(5)                      # 25

# equivalent named function:
def square(x): return x ** 2
```

Lambdas jidrawwu bħala **argumenti inline** għal funzjoniet oħra, speċjalment bħala sort/filter keys:

```python
people.sort(key=lambda p: p.age)            # sort by an attribute
sorted(words, key=lambda w: len(w))          # sort by length
max(items, key=lambda x: x.score)            # find max by a criterion
```

## map — applikaw funzjoni għal kull element

```python
nums = [1, 2, 3, 4]
list(map(lambda x: x ** 2, nums))   # [1, 4, 9, 16]
# more Pythonic alternative — a comprehension:
[x ** 2 for x in nums]               # [1, 4, 9, 16]
```

## filter — żommu elements li jgħaddu test

```python
list(filter(lambda x: x % 2 == 0, nums))   # [2, 4]
# comprehension equivalent:
[x for x in nums if x % 2 == 0]             # [2, 4]
```

## reduce — folder l-iterable f'valur waħdija

```python
from functools import reduce
reduce(lambda acc, x: acc + x, nums, 0)     # 10 (sum)
# but built-ins are clearer when they exist:
sum(nums)                                    # 10
```

## Il-preferenza Pythonic

```text
For map/filter, COMPREHENSIONS are usually more readable and idiomatic:
  map(f, xs)            →  [f(x) for x in xs]
  filter(pred, xs)      →  [x for x in xs if pred(x)]
Lambdas are best for short inline keys (sort/max/filter), NOT complex logic.
```

Guido (il-kreatur ta' Python) u l-komunità ġeneralment jippreferu comprehensions fuq `map`/`filter` għal readability; `reduce` anke tneqliet barra minn builtins. Iżda lambdas bħala funzjoniet `key=` jibqgħu idiomatic u komuni.

## Għaliex hija importanti

Hawwa tools funzjonali jippermettulek tesprimi transformations u filters bi tqassir.

Filwaqt li Python *jista'* jinkiteb b'mod funzjonali, l-għażla idiomatic normalment hija **comprehension** fuq `map`/`filter` għal readability, u built-in (`sum`, `max`, `min`) fuq `reduce`.

Il-post fejn lambdas verament jidrawwu huma bħala funzjoniet inline żgħar li jgħaddu lil `sort`/`max`/`min`/`filter` bħala `key`.

L-fahim tal-isqin — u l-għarfien tal-preferenza Pythonic għal comprehensions u built-ins — għinuk tikteb kodiċi nadif, idiomatic u taqra l-kodiċi stil funzjonali li jidher f'proġetti reali.