con­text-math­sets – Set no­ta­tion in ConTeXt

Type­set good-look­ing set no­ta­tion (e.g., {x|x \in Y}), as well as sim­i­lar things such as Dirac bra-ket no­ta­tion, con­di­tional prob­a­bil­i­ties, etc.
The pack­age is at least in­spired by braket.