A Taste of TeX4ht Configurations-cont

Explanation:

1. The configuration \Configure{over} {...} {...} prepends and appends the \over with the given arguments

2. The \Send{GROUP}{0}{...} sends its argument backward to the start of the current group

3. The \Send{EndGROUP}{0}{...} sends its argument forward to the end of the current group

4. Upon insertion into {...\over...}:

   {...         \Send{GROUP}{0}{\string\frac\l:brace}         \over         \HCode{\r:brace\l:brace}         \Send{EndGROUP}{0}{\r:brace}         ...}

5. After sending:

   {\frac\l:brace ...         \over         \r:brace\l:brace  ...\r:brace}

6. The braces ‘{’ and ‘}’, and the command \over, do not introduce content

   \frac\l:brace ...\r:brace\l:brace ...\r:brace