nested-function

Let we have this code: def big_function(): def little_function(): ....... ......... The Python documentation says about def statement: A function definition is an executable statement. Its execution binds the function name... So, the question is: Does def little_function() execute every time when big_function is invoked? Question is about def statement exactly, not the little_function() body. You can check the bytecode with the dis module: >>> import dis >>> def my_function(): ... def little_function(): ... print "Hello, World!" ... ... >>> dis.dis(my_function) 2 0 LOAD_CONST 1 (<code object

I am trying to understand, how exactly variable binding in python works. Let's look at this: def foo(x): def bar(): print y return bar y = 5 bar = foo(2) bar() This prints 5 which seems reasonable to me. def foo(x): def bar(): print x return bar x = 5 bar = foo(2) bar() This prints 2, which is strange. In the first example python looks for the variable during execution, in the second when the method is created. Why is it so? To be clear: this is very cool and works exactly as I would like it to. However, I am confused about how internal bar function gets its context. I would like to understand

In C the following code works in gcc. int foo( int foo_var ) { /*code*/ int bar( int bar_var ) { /*code*/ return bar_var; } return bar(foo_var); } How can I achieve the same functionality of nested functions in C++ with the gcc compiler? Don't mind if this seems like a beginner question. I am new to this site. Turn your function into a functor as Herb Sutter suggests in this article Local functions are not allowed in C++, but local classes are and function are allowed in local classes. So: int foo( int foo_var ) { /*code*/ struct local { static int bar( int bar_var ) { /*code*/ return bar_var;

I am trying to call a function within a function using sql on postgres 9.3. This question is related to another post by me . I have written the below function. So far I have failed to incorporate any kind of save-output (COPY) statement, so I am trying to work around this by creating a nested function print-out function. CREATE FUNCTION retrieve_info(TEXT, TEXT) RETURNS SETOF retrieve_info_tbl AS $$ SELECT tblA.id, tblA.method, tblA.species, tblA.location FROM tblA WHERE method=$1 AND species=$2 GROUP BY id, method, species ORDER BY location $$ LANGUAGE 'sql'; The above function works. An

I'd like to have variable defined in the nesting function to be altered in the nested function, something like def nesting(): count = 0 def nested(): count += 1 for i in range(10): nested() print count When nesting function is called, I wish it prints 10, but it raises UnboundLocalError. The key word global may resolve this. But as the variable count is only used in the scope of nesting function, I expect not to declare it global. What is the good way to do this? In Python 3.x, you can use the nonlocal declaration (in nested ) to tell Python you mean to assign to the count variable in nesting

I'm just learning some Swift and I've come across the section that talks about nesting functions: Functions can be nested. Nested functions have access to variables that were declared in the outer function. You can use nested functions to organize the code in a function that is long or complex. From here So if the purported benefit is to "organize the code", why not just have the nested function independently, outside of the outer function? That, to me, seems more organized. The only benefit I can discern is that you "have access to variables that were declared in the outer function", but this

def maker(n): def action(x): return x ** n return action f = maker(2) print(f) print(f(3)) print(f(4)) g = maker(3) print(g(3)) print(f(3)) # still remembers 2 Why does the nested function remember the first value 2 even though maker() has returned and exited by the time action() is called? You can see it as all the variables originating in the parent function being replaced by their actual value inside the child function. This way, there is no need to keep track of the scope of the parent function to make the child function run correctly. See it as "dynamically creating a function". def maker