DMN16 — Binary operators should not return null

Here, I am considering the following operators: =, <, >, not(), and, or, in, between

When considering FEEL for low-codes applications, we should expect these binary operators to always return true or false. Currently, when there is typing error, it returns null.

ex:
"a" = 1 => null
false and "a" => null
"a" in [0..100] => null
...

Alternative B-FEEL dialect with a single definition of null

In FEEL, the null value is used to both represent missing data or an execution error. We are proposing that null should be used only to represent missing data. All operations and built-in functions that return null in FEEL when an error occurs have their semantic modified to return a non-null value.