stringstrings – String manipulation for cosmetic and programming application

The pack­age pro­vides a large and sundry set of macros for the ma­nip­u­la­tion of strings. The macros are de­vel­oped not merely for cos­metic ap­pli­ca­tion (such as chang­ing the case of let­ters and string sub­sti­tu­tion), but also for pro­gram­ming ap­pli­ca­tions such as char­ac­ter look-ahead, ar­gu­ment pars­ing, con­di­tional tests on var­i­ous string con­di­tions, etc.
The macros were de­signed all to be ex­pand­able (note that things such as \up­per­case and \low­er­case are not ex­pand­able), so that the macros may be strung to­gether se­quen­tially and nested (af­ter a fash­ion) to achieve rather com­plex ma­nip­u­la­tions.