## Macro: COMMON-LISP:DEFINE-MODIFY-MACRO [![package](https://img.shields.io/badge/Package-COMMON--LISP-5f9ea0.svg?style=social&colorA=999999)](../) [![type](https://img.shields.io/badge/Type-Macro-5f9ea0.svg?style=social&colorA=999999)](../#macro) [![clhs](https://img.shields.io/badge/CLHS-DEFINE--MODIFY--MACRO-5f9ea0.svg?style=social&colorA=999999)](http://www.lispworks.com/documentation/HyperSpec/Body/m_defi_2.htm) > Creates a new read-modify-write macro like PUSH or INCF. ### Lambda list ```cl (sb-impl::name sb-impl::lambda-list function &optional sb-impl::doc-string) ```