If¶
Evaluates a condition between inputs A and B and routes the flow accordingly. It can either forward one of two inputs (TRUE_IN or FALSE_IN) or output a boolean result. Supports lazy evaluation so only the inputs needed for the chosen condition are computed.
Usage¶
Use this node to branch logic in a workflow. Choose a condition (e.g., equality, comparison, containment, identity, bitwise, or a custom expression). If you enable 'Return Inputs', the node forwards TRUE_IN when the condition is true, otherwise FALSE_IN. If you disable it, the node outputs a boolean. Useful for gating expensive operations, selecting between alternatives, or building complex conditional flows with custom expressions.
Inputs¶
| Field | Required | Type | Description | Example |
|---|---|---|---|---|
| condition | True | STRING | Select the condition to evaluate. Options: A is TRUE, B is TRUE, A is NONE, B is NONE, A == B, A != B, A > B, A >= B, A < B, A <= B, A is B, A is not B, A in B, B in A, A & B, A \| B, A ^ B, CUSTOM. | A == B |
| require_inputs | True | BOOLEAN | If true (Return Inputs), forwards TRUE_IN or FALSE_IN based on the evaluated condition. If false (Return Boolean), returns a boolean result instead. | True |
| NOT | True | BOOLEAN | Invert the result after evaluation. For booleans, applies logical NOT; for non-boolean results that support it, applies bitwise inversion. | False |
| custom_expression | True | STRING | Expression used only when condition is CUSTOM. You can refer to A and B (case-insensitive) and named global variables from memory storage nodes. Most standard Python-like expressions are supported. | 2*a == 5*b + 2 |
| A | False | ANY | First input to evaluate. Only required/used if the selected condition (or custom expression) references A. | 42 |
| B | False | ANY | Second input to evaluate. Only required/used if the selected condition (or custom expression) references B. | 100 |
| TRUE_IN | False | ANY | Value forwarded to the output when the condition evaluates to true. Only used when require_inputs is true. | forward this value if true |
| FALSE_IN | False | ANY | Value forwarded to the output when the condition evaluates to false. Only used when require_inputs is true. | forward this value if false |
Outputs¶
| Field | Type | Description | Example |
|---|---|---|---|
| * | ANY | If require_inputs is true, forwards TRUE_IN when the condition is true, otherwise FALSE_IN. If require_inputs is false, outputs a boolean result. | True |
Important Notes¶
- Lazy evaluation: Only inputs referenced by the selected condition (or present in the custom expression) are evaluated, allowing you to avoid unnecessary computation.
- Return mode: With 'Return Inputs' enabled (require_inputs = true), TRUE_IN/FALSE_IN must be provided; otherwise, the node returns a boolean.
- Custom expressions: When using CUSTOM, ensure A and/or B are provided if referenced in the expression. You can also reference global memory variables by name.
- Inversion behavior: NOT inverts booleans using logical NOT; for non-boolean results supporting inversion, bitwise NOT is applied.
- Comparison handling: Equality and inequality are designed to work with a variety of data types, including tensors and standard Python types.
- Type compatibility: For operators like >, <, &, |, ^, ensure A and B support those operations; otherwise, the condition will fail and default to false.
Troubleshooting¶
- No output forwarded when 'Return Inputs' is on: Connect both TRUE_IN and FALSE_IN. If one branch isn't connected and is selected by the condition, the node cannot forward a value.
- custom_expression disabled: Set condition to CUSTOM to enable editing and use of the custom expression input.
- Condition always false in CUSTOM: Verify A and/or B are connected if referenced (e.g., expression contains 'a' or 'b'), and check for typos in variable names.
- Type errors (e.g., '>' not supported): Use compatible types for the chosen operator or switch to a condition that matches your data types.
- Unexpected inversion: If NOT is enabled and the result is non-boolean, bitwise inversion is applied which may not match logical expectations. Disable NOT or ensure the result is boolean.
- Containment checks fail ('A in B' / 'B in A'): Ensure the right-hand operand supports containment (e.g., list, set, dict, string) and that types are comparable.