If you read the previous chapter Use sub chain and then read this chapter, you will think that using sub variables is actually easier than using sub chain!

LiteFlow's new expression syntax lets you define sub variables directly in your rules!

we still look at this example

Flow chart

If we define subprocess variables, we can write:

<chain>
    t1 = THEN(C, WHEN(J, K));
    w1 = WHEN(Q, THEN(P, R)).id("w01");
    t2 = THEN(H, I);
    
    THEN(
        A, B,
        WHEN(t1, D, t2),
        SWITCH(X).to(M, N, w1),
        Z
    );
</chain>