patch – Patch loaded packages, etc.

The pack­age de­fines macros that al­low patch­ing of ex­ist­ing com­mands, spec­i­fy­ing those parts of the ex­ist­ing macro to be re­placed, along with the re­place­ments. Thus it pro­vides more so­phis­ti­cated ma­nip­u­la­tion than a pack­age like patchcmd, which only per­mits mod­i­fi­ca­tion by adding com­mands at the be­gin­ning or end of an ex­ist­ing def­i­ni­tion.
The pack­age is dis­tributed in a rel­a­tive of LaTeX doc for­mat: it will run un­mod­i­fied, though it ben­e­fits from doc­strip treat­ment.