Re: default for ma@symmetric

Neil:

Thanks for your comments, as always.

> The operator dictionary only lists a value when the value is true -- if a value isn't given and it is relevant, then it's value is false. There is some text a few paragraphs above that explain that.

The text says

	"Boolean valued attributes such as stretchy are specified together in the final Properties column by listing
	the attribute name if its value should be set to true by the dictionary.

	Any attribute not listed for some entry has its default value, which is given in parentheses in the table of
	attributes in Section 3.2.5 Operator, Fence, Separator or Accent <mo>"

which is why I wanted to understand the default better.  This seems to say that when the value is true when it is listed, and the default value otherwise.  (Presumably, this would be false.)  It is not clear how to specify a false property when the default is true (though I would think symmetric=false would be one way, based on the non-boolean properties listed in that column).

In any case, I'm afraid it is still not clear to me.  It would have made sense to have had the property column work as you suggest, but that doesn't seem to be what is documented.

Davide