1 This LaTeX package provides macros to typeset bra-ket notation, as
2 well as set specifiers, with a single ("|") or a double ("||" or
3 ("\|") vertical bar specifier in between two bracketed parts. Each
4 macro comes in a fixed-size version and an expanding version. If the
5 package finds itself operating under e-tex, it uses the extended
6 primitive \middle for more reliable results.