Repeat Action (Loop)#

The Repeat action (internally called Loop) allows you to iterate over a collection of items—such as rows in a child table or results from a Query Records block—and execute a specific execution path for each item.

How it Works#

1. Iterator: You define which list to iterate over (e.g., doc.items or vars.query_results).
2. Item Alias: You define a name for the current item (e.g., item or row). This variable is updated in every iteration.
3. The Loop Path: The engine follows the True branch for every item in the list.
4. The Exit Path: Once all items have been processed, the engine follows the False branch to continue the rest of the rule.

Configuration#

1. Iterator#

An expression that resolves to a list or tuple.

• Example: doc.items (standard Frappe child table).
• Example: vars.matching_invoices (result from a previous Query Records block).

2. Item Alias (Return Variable)#

The name of the variable that will hold the current item during each iteration.

• Default: item.
• Accessible as: vars.item (or your custom name).

3. Loop Metadata#

Inside the loop, FlexiRule providing a special vars.loop object with useful metadata:

• vars.loop.index: The current iteration index (starting from 0).
• vars.loop.length: The total number of items in the list.
• vars.loop.first: Boolean, true if this is the first iteration.
• vars.loop.last: Boolean, true if this is the last iteration.

Execution Semantics#

• Top-to-Bottom Iteration: The loop processes items in the order they appear in the input list.
• State Preservation: Variables modified inside the loop persist across iterations and after the loop completes.
• Safety: FlexiRule’s global iteration limit (1000 steps) applies to loops to prevent accidental infinite recursion.

Example: Apply Discount to All Items#

Scenario: You want to set a 10% discount on every row in a Sales Order items table.

1. Repeat Block:
   • Iterator: doc.items
   • Alias: row
   • Next (True): Connect to an Assignment block.
   • Next (False): Connect to the rest of your rule (e.g., a “Notify” block).
2. Assignment Block:
   • Target: vars.row.discount_percentage
   • Value: 10
   • Next: Connect back to the Repeat block to continue iteration.

Best Practices#

• Connect Back: Ensure the last node in your loop path connects back to the Repeat block to trigger the next iteration.
• Use Sub-rules for Complexity: If the logic inside your loop is more than 3-4 nodes, move it into a Sub-rule for better readability and maintainability.
• Filtering: Instead of looping over a large list and using a Condition block inside to skip items, try to filter the list before it reaches the loop (e.g., using a Query Records with specific filters).

Common Mistakes#

• Wrong Path: Forgetting to connect the final step of the loop back to the Repeat node. If you don’t connect back, the loop will only run for the first item.
• Variable Overlap: If you have nested loops, ensure they use different Item Aliases to avoid one loop overwriting the data of another.