Dear Hans and others,

I'm usually use the \big, \Big, \bigg etc to get the size of parentheses, brackets and braces to be the size I want. I realize that the fences machinery is probably a cleaner way of doing this.

I tried it a bit, and it usually gives the result I like. But sometimes not, and it seems that the way to change the size of the parentheses/brackets/braces is to use the factor key.

1) Are the different options none, auto NUMBER explained somehere?

2) Could one have, for exceptional cases where the default is not satisfactory, a keyword like factor=big for example, to get the same size as if one would have used \big?

I am a bit confused. See the example below, with output (from latest standalone) attached.

/Mikael

PS: I would suggest to have

 italic       = { feature = 'ss01', value = 1, comment = "Mathematical Alternative Lowercase Italic" },

set in lucida-opentype-math.lfg. In all books (on math) I have seen, I think this is what is used.

%%% Example file:

\setupbodyfont[lucidaot]

\definemathfence[Set][left="007B,right="007D,command=yes]

\startbuffer

\startformula

\Set{x\in\mathbb R~:~x^2=1}

\stopformula

\stopbuffer

\startTEXpage[offset=3bp]

\startformula

\{x\in\mathbb R~:~ x^2=1\}%Too small

\stopformula

\startformula

\bigl\{x\in\mathbb R~:~ x^2=1\bigr\}%I like this one

\stopformula

\startformula

\Bigl\{x\in\mathbb R~:~ x^2=1\Bigr\}%Too big

\stopformula

\getbuffer

\setupmathfence[Set][factor=1]%I like this one

\getbuffer

\setupmathfence[Set][factor=auto]%Too big

\getbuffer

%\setupmathfence[Set][factor=big]%Perhaps this could work? Or size=big or something

%\getbuffer

\stopTEXpage