This module deals with creating delimiters of various sizes. The TeXbook discusses these routines on page 441-442, in the "Another subroutine sets box x to a specified variable delimiter" paragraph.
There are three main routines here.
makeSmallDelim makes a delimiter in the
normal font, but in either text, script, or scriptscript style.
makeLargeDelim makes a delimiter in textstyle, but in one of the Size1,
Size2, Size3, or Size4 fonts.
makeStackedDelim makes a delimiter out of
smaller pieces that are stacked on top of one another.
The functions take a parameter
center, which determines if the delimiter
should be centered around the axis.
Then, there are three exposed functions.
sizedDelim makes a delimiter in
one of the given sizes. This is used for things like
customSizedDelim makes a delimiter with a given total height+depth. It is
called in places like
leftRightDelim makes an appropriate
delimiter which surrounds an expression of a given height an depth. It is