> ## Documentation Index
> Fetch the complete documentation index at: https://docs.abbyy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Existence condition

> Existence-condition operations in NLP Extraction Rules code — check object existence or absence, assign variable names, and combine conditions.

| Operation        | Syntax        | Description                                                                                                                                                                                           | Example                                                                                                                   |
| :--------------- | :------------ | :---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | :------------------------------------------------------------------------------------------------------------------------ |
| object existence | `object_name` | Checks that an object exists.                                                                                                                                                                         | `Root.Group` Checks that the Group search element has been found.                                                         |
| variable         | `:`           | A colon is used to assign a name to the object that follows it. **Note:** The variable will be available only within that same rule, that is, until the right-hand part is finished with a semicolon. | `t: Root.Group` Checks that the Group search element has been found and assigns it to a new variable t.                   |
| object absence   | `~`           | A tilde sign negates a condition or specifies the absence of an object. Note that you can't assign a name if the object is specified as non-existent. `// INVALID STATEMENT:` `t: ~Root.Element`      | `~Root.Element1` Checks that the Element1 search element has not been found.                                              |
| logical AND      | `,`           | A comma is used as a logical conjunction.                                                                                                                                                             | `Borrower.Name, Borrower.Address` Checks that both the Name and Address search elements were found in the Borrower group. |