# rule_variable · FT4 Rell API · Chromia Docs (concept)

> enum rule_variable The variables that an auth descriptor rule can check against. Entries block_height block_time op_count

Source: https://docs.chromia.com/pages/ft4-rell/-f-t4-library/lib.ft4.core.accounts/rule_variable/

ENUM

# rule\_variable

```signature
enum rule_variable
```

[Source](https://gitlab.com/chromaway/ft4-lib/-/blob/development/rell/src/lib/ft4/core/accounts/auth_descriptor_rule_expression.rell#lines-2)

The variables that an auth descriptor rule can check against.

## Entries

`block_height`

`block_time`

`op_count`

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-rell/-f-t4%20-library/lib.ft4.core.accounts/rule_variable/index.html)Generated API reference, mirrored from the live docs