### Perform for loop

The For control node is a convenient node that enable users to mimic classical for instruction of C-language.

The node layout has threee blocks plus an input counter value i_begin provided by a previous node of the composition. This counter value can be incremented and used for test stop criterion inside dedicated blocks, namely the conditional block and the increment block. The body of the loop is defined by the subcomposition standing inside the body block.

During execution, the condition is firstly tested, then if it is valid then the body composition is executed and eventually, the incrmental process is performed.

The last value of the loop counter can be used further in the composition thanks to i_end port.