Flexible Argument Strategies
Advanced Function Design Techniques
Flexible argument strategies enable developers to create more adaptable and reusable functions in Python.
1. Function Decorators with Arguments
Decorators can modify function behavior while maintaining argument flexibility.
def logger(func):
def wrapper(*args, **kwargs):
print(f"Calling {func.__name__}")
return func(*args, **kwargs)
return wrapper
@logger
def calculate(x, y, operation='add'):
if operation == 'add':
return x + y
elif operation == 'multiply':
return x * y
print(calculate(5, 3))
print(calculate(5, 3, operation='multiply'))
2. Type Hinting and Flexible Arguments
Python 3.5+ supports type hints for more robust argument handling.
from typing import Union, List, Optional
def process_data(
data: Union[int, List[int]],
multiplier: Optional[float] = 1.0
) -> List[float]:
if isinstance(data, int):
return [data * multiplier]
return [item * multiplier for item in data]
print(process_data(5))
print(process_data([1, 2, 3], multiplier=2.0))
Argument Strategy Flow
graph TD
A[Function Design] --> B{Argument Strategy}
B --> |Positional| C[Fixed Arguments]
B --> |Keyword| D[Named Arguments]
B --> |Flexible| E[*args /**kwargs]
B --> |Type Hints| F[Type Checking]
Argument Handling Strategies
Strategy |
Flexibility |
Use Case |
Complexity |
Positional |
Low |
Simple functions |
Easy |
Keyword |
Medium |
Configuration |
Moderate |
*args/**kwargs |
High |
Dynamic inputs |
Complex |
Type Hints |
Robust |
Type Safety |
Advanced |
3. Partial Function Application
The functools.partial
allows creating new functions with preset arguments.
from functools import partial
def power(base, exponent):
return base ** exponent
square = partial(power, exponent=2)
cube = partial(power, exponent=3)
print(square(4)) ## 16
print(cube(2)) ## 8
4. Dynamic Argument Validation
Create flexible functions with custom argument validation.
def validate_args(func):
def wrapper(*args, **kwargs):
if not all(isinstance(arg, (int, float)) for arg in args):
raise TypeError("Arguments must be numeric")
return func(*args, **kwargs)
return wrapper
@validate_args
def safe_calculate(x, y, z=0):
return x + y + z
print(safe_calculate(1, 2, 3))
## Raises TypeError if non-numeric arguments are passed
Best Practices for Flexible Arguments
- Use type hints for clarity
- Implement decorators for cross-cutting concerns
- Leverage
*args
and **kwargs
judiciously
- Validate arguments to ensure function reliability
By mastering these flexible argument strategies, you'll write more dynamic and adaptable code in your LabEx programming projects.