[SOLVED] Is statement in for each loop executed each iteration?

Is statement in for each loop executed each iteration?

I have a function which returns a container. Let's just call it 'Container'.

Container GenerateRandomContainer() { ... }

This function will generate a container with random elements that are different each call.

When I iterate through this container using a for each loop like this:

for(Element e : GenerateRandomContainer()) { ... }

Will it generate a new Container each iteration or will it generate only one when the for each loop is entered?

Solution

The range-based for loop is equivalent as follows:

{
    auto && __range = range_expression ; 
    auto __begin = begin_expr ;
    auto __end = end_expr ;
    for ( ; __begin != __end; ++__begin) { 
        range_declaration = *__begin; 
        loop_statement 
    } 
}

Note the 1st statement auto && __range = range_expression ; (range_expression will be GenerateRandomContainer() for your code); that means the Container will be generated only once, and iterates on all the elements of it.