Operator Dictionary. Non-Normative

Hello,



I was wandering the exact meaning of "non-normative" appearing in the
Operator Dictionary appendix.



As you already know, at WIRIS, we do edition/input of MathML. We decided
that parenthesis, among other symbols, are no stretchy by default due to
practical reasons. If <mo>(</mo> and <mo>)</mo> were stretchy, we needed
some kind of predictive tool to match opening with closing parenthesis.
And because we just decided we did not wanted to pass as an oracle,
parenthesis ended up being no stretchy.



Daniel Marques from WIRIS