Loops, Branches, and Conditional Logic
In Xircuits, we have provided the controlflow component library which implements loops, branches, and conditional logic operations. Here are some common components to perform them: the BranchComponent, LoopComponent, ForEach, and ComparisonComponent.
Branching If Logic with BranchComponent
The BranchComponent allows you to create branches in your workflow based on a condition, similar to an if-else statement in traditional programming.
Consider the following workflow:
The BranchComponent will alter its behavior depending on the condition inPort. In this case, as a Literal True is connected to the BranchComponent, it will execute the Print component which is connected to the "This will be printed if the condition is true!" Literal String. Finally, as with all branch components, it will go to the default flow port after completing the branch execution flow and execute one additional Print component.
The output of the above workflow is shown below.
Expected Output
======================================
__ __ ___ _ _
\ \ \ \/ (_)_ __ ___ _ _(_) |_ ___
\ \ \ /| | '__/ __| | | | | __/ __|
/ / / \| | | | (__| |_| | | |_\__ \
/_/ /_/\_\_|_| \___|\__,_|_|\__|___/
======================================
Xircuits is running...
Executing: Example
Executing: Print
This will be printed if the condition is True!
Executing: Print
Finally, this will be executed once the final branch flow is complete!
Finished Executing
If you would like more examples of BranchComponent, ControlflowBranch.xircuits workflow is something you can try.
Looping with LoopComponent
The LoopComponent enables repetitive execution of a workflow segment based on a condition, similar to a while loop.
Consider the example ControlflowLoop.xircuits:
LoopComponent will keep looping as long as the condition is set to be True.
Expected Output
======================================
__ __ ___ _ _
\ \ \ \/ (_)_ __ ___ _ _(_) |_ ___
\ \ \ /| | '__/ __| | | | | __/ __|
/ / / \| | | | (__| |_| | | |_\__ \
/_/ /_/\_\_|_| \___|\__,_|_|\__|___/
======================================
Xircuits is running...
Executing: ControlflowLoop
Executing: Print
Dormammu
Executing: Print
I've come to bargain!
Executing: SleepComponent
Sleeping for 1 seconds.
Executing: Print
I've come to bargain!
Executing: SleepComponent
Sleeping for 1 seconds.
...
As shown from the output, this workflow will continue indefinitely as the condition is always True. What if you want to set a set number of loops? You can use the ForEach component mix a Variable component and a Comparison component, which will be covered next.
Iterating with ForEach Component
The ForEach component iterates over a list of items, executing a workflow segment for each item, similar to a for loop. Consider the following workflow:
In this workflow, the ForEach component will iterate through each item in the list. The item and the index are printed one after the other.
Expected Output
======================================
__ __ ___ _ _
\ \ \ \/ (_)_ __ ___ _ _(_) |_ ___
\ \ \ /| | '__/ __| | | | | __/ __|
/ / / \| | | | (__| |_| | | |_\__ \
/_/ /_/\_\_|_| \___|\__,_|_|\__|___/
======================================
Xircuits is running...
Executing: ForEachComponentExample
Executing: Print
sugar
Executing: Print
0
Executing: Print
spice
Executing: Print
1
Executing: Print
and everything nice
Executing: Print
2
Executing: Print
also chemical X
Executing: Print
3
Finished Executing
Comparison and Conditional Logic
The ComparisonComponent performs comparisons between two values and returns a boolean result, useful for creating conditions in branches and loops. Consider the following advanced example:
In this workflow, we first define a boolean variable called is_running using DefineVariableComponent. This boolean is the condition of looping for the LoopComponent. The workflow then defines a counter that decreases each step. Then finally using the ComparisonComponent, we define only when the counter is less than 1, is_running will be False.
Expected Output
======================================
__ __ ___ _ _
\ \ \ \/ (_)_ __ ___ _ _(_) |_ ___
\ \ \ /| | '__/ __| | | | | __/ __|
/ / / \| | | | (__| |_| | | |_\__ \
/_/ /_/\_\_|_| \___|\__,_|_|\__|___/
======================================
Xircuits is running...
Executing: ControlflowBranch
Executing: Print
You can chain multiple branches together!
Executing: Print
The 2nd branch is True!
Executing: Print
Finally, this will be executed once the final branch flow is complete!
Finished Executing
These are just some of the controlflow components that are available, if you are a developer, you can even create your own branch component. For more technical details on how these components work, you can refer to the branch components reference documentation.