Function check_same_polynomial 

pub fn check_same_polynomial(
    predicate: &Predicate,
    file: &str,
) -> Result<(), Error>

Checks that the main form of predicate is a nonzero polynomial and, if the predicate has an exact form, that both forms are the same polynomial.

Errors

Returns an error at the position of the predicate’s name when the main form expands to zero, at the position of the exact form’s name when it expands to a different polynomial, and at the position of the form when canonical cannot expand it.