11 SXEmacs Specific Style

This section was lifted almost word for word from the XEmacs CODING-STANDARDS by Ben Wing.

Specially-prefixed functions/variables:

• All global C variables whose value is constant and is a symbol begin with a capital Q, e.g. Qkey_press_event. (The type will always be Lisp_Object.)
• All other global C variables whose value is a Lisp_Object (this includes variables that forward into Lisp variables plus others like Vselected_console) begin with a capital V.
• No C variables whose value is other than a Lisp_Object should begin with a capital V. (This includes C variables that forward into integer or boolean Lisp variables.) All global C variables whose value is a struct Lisp_Subr begin with a capital S. (This only occurs in connection with DEFUN ()).
• All C functions that are Lisp primitives begin with a capital F, and no others should begin this way.

Functions for manipulating Lisp types:

• Any function that creates an empty or mostly empty Lisp object should begin allocate_(). (*Not* make_().) (Except, of course, for Lisp primitives, which usually begin Fmake_()).
• Any function that converts a pointer into an equivalent Lisp_Object should begin make_().
• Any function that converts a Lisp_Object into its equivalent pointer and checks the type and validity of the object (e.g. making sure it’s not dead) should begin decode_().
• Any function that looks up a Lisp object (e.g. buffer, face) given a symbol or string should begin get_(). (Except, of course, for Lisp primitives, which usually begin Fget_()).

Other:

Any header-file declarations of the sort

   struct foobar;

go into the types section of lisp.h.