A closure is a function object.A closure remembers values from the enclosing lexical scope even when the program is no longer in the enclosing scope.
Inner function in a nested function can be called as a closure,but not always.
A closure occurs when a function has access to local variables from an enclosing function that has completed execution.
Example:def make_out_love(x):
def love():
print(x)
return love
love = make_out_love('Tonight We are making love')
love()
A nested function is not closure if:
1.Nested functions dont access variables that are local to enclosing scopes.
2.If Nested functions are executed outside the scope.
Example:def make_out_love(x):
def love(x=x):
print(x)
return love
love = make_out_love('Tonight We are making love')
love()
1.Closures are functions that inherit variables from enclosing environment.
2.Function should use free variables in order to be a closure
3.The attribute __closure__ saves the free variables.
4.Every function in python has closure attributes but it does not save any content if there are no free variables.
5.The closure attribute(__closure__) returns a tuple of cell objects which contain details of the variables defined in the enclosing scope.
Note:Every Function has a __closure__ attribute,if there is no data for __closure__ attribute it is assigned None.
Why to and who use Closures?
1.Decorators in python makes extensive use of closures.
Inner function in a nested function can be called as a closure,but not always.
A closure occurs when a function has access to local variables from an enclosing function that has completed execution.
Example:def make_out_love(x):
def love():
print(x)
return love
love = make_out_love('Tonight We are making love')
love()
A nested function is not closure if:
1.Nested functions dont access variables that are local to enclosing scopes.
2.If Nested functions are executed outside the scope.
Example:def make_out_love(x):
def love(x=x):
print(x)
return love
love = make_out_love('Tonight We are making love')
love()
1.Closures are functions that inherit variables from enclosing environment.
2.Function should use free variables in order to be a closure
3.The attribute __closure__ saves the free variables.
4.Every function in python has closure attributes but it does not save any content if there are no free variables.
5.The closure attribute(__closure__) returns a tuple of cell objects which contain details of the variables defined in the enclosing scope.
Note:Every Function has a __closure__ attribute,if there is no data for __closure__ attribute it is assigned None.
Why to and who use Closures?
1.Decorators in python makes extensive use of closures.
