C<X> expand( C<X> container, F<C,X,Y> functor );

where :

• C is a container type (template)
• F is the functor type (template)
• X is the type of objects in the input container

A container of type C holding objects of type X

Calls the functor for each element in the input container and merges the resulting collections into a single one.

// source : examples/expand_example.cpp
#include <iostream>
#include <list>
#include <algorithm>
#include "sftl.h"
 
using namespace std;
 
// collapses a number into digits
 
list<short> get_digits( int x ) {
    list<short> digits;
    while (x>0) {
        digits.push_front( x % 10 );
        x/=10;
    }
    return digits;
}
 
void print( short x ) { cout << x << endl; }
 
int main() {
 
    // create vector of numbers
    int numbers [] = {101,24,55,71};
    list<int> v_numbers( &numbers[0], &numbers[4] );
 
    // obtain all digits
    list<short> all_digits = expand( v_numbers, get_digits );
 
    // print them
    apply( all_digits, print ); // prints 1 0 1 2 4 5 5 7 1
}