List to Accumulation¶
Converts an input into an accumulation structure. If the input is a list, it becomes the accumulation contents directly; if it is a single value (not a list), it is wrapped into a one-element accumulation.
Usage¶
Use this node when you need to initialize or reset an accumulation from an existing list, or when you want to standardize a single value into an accumulation for downstream list/accumulation operations. Commonly used before nodes that operate on the ACCUMULATION type (e.g., get length, get/set item, head/tail).
Inputs¶
| Field | Required | Type | Description | Example |
|---|---|---|---|---|
| list | True | WILDCARD | The value to convert. If it is a Python list, its elements become the accumulation. Any non-list value is wrapped as a single element. | [1, 2, 3] or "hello" |
Outputs¶
| Field | Type | Description | Example |
|---|---|---|---|
| accumulation | ACCUMULATION | An accumulation object containing the input elements under the 'accum' key. | {"accum": [1, 2, 3]} |
Important Notes¶
- This node treats only Python lists as lists; other iterables like tuples are considered single values and will be wrapped as one element.
- If the input is already an accumulation object (a dict with an 'accum' key), it will be wrapped as a single element rather than merged.
- Passing None results in an accumulation with a single None element.
- On error, the node returns an empty accumulation: {"accum": []}.
Troubleshooting¶
- Input is a tuple and doesn't expand: Convert your tuple to a list before this node if you want its elements to populate the accumulation.
- Already have an ACCUMULATION and want a list: Use 'Accumulation to List' to extract elements instead of passing it here.
- Unexpected empty result: Check for upstream errors or invalid types; the node returns {"accum": []} on exceptions.