rego.v1: rego_parse_error: rule must have value assignment and/or body declaration

[anderseknert]

package play

import future.keywords.if

foo(a, b) if {
    f(a)
} else if {
    f(b)
} else := false

f(_)

This policy parses as expected, but chaging the import future.keywords.if to import rego.v1 and re-evaluating renders:

1 error occurred: policy.rego:9: rego_parse_error: rule must have value assignment and/or body declaration

(line 9 is } else := false)

I don't think this is expected. If it is, it's not clear to me what should be changed.

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