The Basic syntax documentation does not match with actual output

[prithvipal]

I am new to OPA and I am learning Rego from the official document.

If we evaluate v, the result is undefined because the body of the rule never evaluates to true. As a result, the document generated by the rule is not defined.

But when I run the following statement in interactive shell:

v if "hello" == "world"

Then I am getting error 1 error occurred: 1:1: rego_unsafe_var_error: var v is unsafe where the document say it will show as undefined decision.

Is this document up to date?

[anderseknert]

Good morning! Using if (and other keywords, like contains) requires first having done an import rego.v1:

❯ opa run
OPA 0.64.1

Run 'help' to see a list of commands and check for updates.

> v if "hello" == "world"
1 error occurred: 1:1: rego_unsafe_var_error: var v is unsafe
> import rego.v1
> v if "hello" == "world"
Rule 'v' defined in package repl. Type 'show' to see rules.
> v
undefined

This is explained later down in the docs at https://www.openpolicyagent.org/docs/latest/policy-language/#rules
But perhaps that section should be moved up to before if is used in an example.