In which order many functions are executed in a python code

[Erik]

On 10/06/17 00:18, Terry Reedy wrote:
> On 6/9/2017 6:00 PM, Erik wrote:
>> On 09/06/17 19:39, sondes kalboussi wrote:
>>> Am a bit confused I was thinking that the order of execution of
>>> functions in a code is from the first to the last function but
>>> sometimes it is the opposite, for instance, some parameters or
>>> outputs from the second function are called in the first one even
>>> thou they are not global, any hints ?
>>
>> As a complete and utter guess, I assume you are talking about 
>> something like:
>>
>> result = func1(1, 2, func2(x, y))
> 
> On the right side of '=', Python evaluates expressions, to the extent 
> possible, left to right.  The result of each evaluation is an object. In 
> the above, the order is func1, 1, 2, func2, x, y, _tem = func2(x, y), 
> func1(1, 2, _tem).  Note that function expressions can be more 
> complicated than just a name, as in func_array[selector].

Terry, how does this help the OP who is obviously a learner, understand 
their problem?

>> In this case, func2() will be called before func1(). This is because 
>> func1() needs three parameters and one of those parameters is the 
>> return value of func2().
> 
> Given r = f[a](1, g[b](c)), your rule above does not determine whether 
> f[a] or g[b] is determined first.  In at least some C implementations, 
> g[b] would be.  Since the call g[b](c) could affect the bindings of f, 
> a, and the result of f[a], the rule that f[a] is calculated before g, b, 
> c, g[b], and g[b](c) may make a real difference.

Terry, how does this help the OP who is obviously a learner, understand 
their problem?

>> Python can not know the return value of func2() without calling it. 
>> Therefore, to be able to call func1() and give it its three 
>> parameters, it must first call func2() to find out what that third 
>> parameter value is.
>>
>> It's equivalent to:
>>
>> func2result = func2(x, y)
>> result = func1(1, 2, func2result)
> 
> Since the func2 call could have the side effect of rebinding 'func1', 
> this is not exactly equivalent.

Whilst this is strictly correct, Terry, how does this help the OP who is 
obviously a learner, understand their problem?

I was trying to help someone by writing in terms I thought would help 
them to understand the question they posed (if I was correct in my 
assumption of what that question actually meant).

Why have you just jumped on everything I've said with responses that are 
really not what someone posting to -list for the first time might even 
understand?

If you want to prove something to me, then send something to me. I 
really don't understand why you would respond in this way.

E.