Function eval_comparison 

pub fn eval_comparison(
    op: BinaryOp,
    left: &Value,
    right: &Value,
    catalog: Option<&dyn EnumLabelCatalog>,
    state: Option<&EnumComparisonState>,
) -> Result<Option<Value>>

Evaluate a scalar enum operator against physical identities. Other operand types remain with the ordinary SQL comparison owner; no label output occurs.