An example to explain the use of Python's lambda statement to declare anonymous functions

The so-called anonymous function means that there is no need to define a function, it can be used like an expression, and there is no need for a function name (many times the name bothers me). Some simple functions are simplified. For example
I need two A function that adds integers is usually defined like this

def add(x, y):
  return x + y

It completes the function I need very well, but now I need a function that adds numbers and strings

def addstr(x, y):
  return x + str(y)

Once again completed my needs, but I suddenly need the function of subtracting and dividing two integers, so the function has to be written down all the time, but using lambda anonymous functions can be used directly

# 相加的实现
f = lambda x, y: x + y
 
f_str = lambda x, y: x + str(y)

Simplifies the operation to make the function simpler, but one disadvantage is poor maintainability. It is not recommended when complex functions are required

lambda [arg1[, arg2, ... argN]]: expression

The following example illustrates the use of lambda statements (no parameters) ).

Python anonymous function lambda example (no parameters) Python

# 使用def定义函数的方法
def true():
  return True
 
#等价的lambda表达式
>>> lambda :True
<function <lambda> at 0x0000000001E42518>
 
# 保留lambda对象到变量中，以便随时调用
>>> true = lambda :True
>>> true()
True
 
# 使用def定义函数的方法
def true():
  return True
  
#等价的lambda表达式
>>> lambda :True
<function <lambda> at 0x0000000001E42518>
  
# 保留lambda对象到变量中，以便随时调用
>>> true = lambda :True
>>> true()
True

The following is another example with parameters.

Python anonymous function lambda example (including parameters) Python

# 使用def定义的函数
def add( x, y ):
  return x + y
 
# 使用lambda的表达式
lambda x, y: x + y
 
# lambda也允许有默认值和使用变长参数
lambda x, y = 2: x + y
lambda *z: z
 
# 调用lambda函数
>>> a = lambda x, y: x + y
>>> a( 1, 3 )
4
>>> b = lambda x, y = 2: x + y
>>> b( 1 )
3
>>> b( 1, 3 )
4
>>> c = lambda *z: z
>>> c( 10, 'test')
(10, 'test')
 
# 使用def定义的函数
def add( x, y ):
  return x + y
  
# 使用lambda的表达式
lambda x, y: x + y
  
# lambda也允许有默认值和使用变长参数
lambda x, y = 2: x + y
lambda *z: z
  
# 调用lambda函数
>>> a = lambda x, y: x + y
>>> a( 1, 3 )
4
>>> b = lambda x, y = 2: x + y
>>> b( 1 )
3
>>> b( 1, 3 )
4
>>> c = lambda *z: z
>>> c( 10, 'test')
(10, 'test')

Does the code look more concise without losing readability?

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