On using several scoped blocks in a C++ function [closed] - c++

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I am starting to be more and more attracted to writing long C++ algorithmic functions using successive scoped blocks, as follows:
void my_algorithm(const MyStruct1 &iparam1, MyStruct2 &oparam2)
{
// First block
MyStruct3 intermediate_var3;
{
double temporary_var;
// Functional step 1.1
// Functional step 1.2
intermediate_var3 = ...
}
// Second block
MyStruct4 intermediate_var4;
{
double temporary_var;
// Functional step 2.1
// Functional step 2.2
intermediate_var4 = ...
}
// Final block
{
int temporary_var;
oparam2 = ...
}
}
I am starting to think it is a good way to clarify the function structure and to limit the scope of temporary variables (such as counters i, j, k etc). I saw that such scope blocks make sense in C functions to enable new declarations (see Why enclose blocks of C code in curly braces?).
In the context of C++, is this good or bad practice ?

Answer 1

This is a clear sign, that you should extract this separate blocks into separate functions.
MyStruct3 DoSth3(params)
{
double temporary_var;
// Functional step 1.1
// Functional step 1.2
return ...
}
MyStruct4 DoSth4(params)
{
double temporary_var;
// Functional step 2.1
// Functional step 2.2
intermediate_var4 = ...
}
void my_algorithm(const MyStruct1 &iparam1, MyStruct2 &oparam2)
{
// First block
MyStruct3 intermediate_var3 = DoSth3(params);
// Second block
MyStruct4 intermediate_var4 = DoSth4(params);
int temporary_var;
oparam2 = ...
}
It may happen, that you'll be worried about DoSth3 and DoSth4 being public, as they should be private in the context of my_algorithm. In such case you can solve it in the following way:
class my_algorithm
{
private:
static MyStruct3 DoSth3(params);
static MyStruct4 DoSth4(params);
public:
static void Perform(const MyStruct1 &iparam1, MyStruct2 &oparam2);
};