Starting from v2.9.0, LiteFlow provides loop expression syntax.

FOR

The FOR loop expression is used for a fixed number of loops. The usual usage is:

<chain name="chain1">
    FOR(5).DO(THEN(a, b));
</chain>

The above expression means that a->b loops 5 times.

If you are not sure how many times to loop when you define the rule, you can also define it like this:

<chain name="chain1">
    FOR(f).DO(THEN(a, b));
</chain>

The f node needs to be For Component, and returns an int loop count. For how to define it, please refer to For component.

WHILE

The WHILE loop expression is used for conditional looping and is usually used as:

<chain name="chain1">
    WHILE(w).DO(THEN(a, b));
</chain>

The w node needs to be While component and returns a boolean value. If it is true, the loop will continue. For how to define it, please refer to While component.

BREAK

LiteFlow also supports the BREAK syntax, which means break out of the loop.

The BREAK keyword can be followed by FOR and WHILE, and is usually used as follows:

<chain name="chain1">
    FOR(f).DO(THEN(a, b)).BREAK(c);
</chain>

<chain name="chain1">
    WHILE(w).DO(THEN(a, b)).BREAK(c);
</chain>

The c node needs to be Break component, returning a boolean value, and exiting the loop if true. For how to define it, please refer to Break component.