SQLite

** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
** @(#) $Id: sqlite.h.in,v 1.455 2009/05/24 21:59:28 drh Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.

** will result in [SQLITE_ERROR] being returned.
**
** The third parameter (nArg)
** is the number of arguments that the SQL function or
** aggregate takes. If this parameter is -1, then the SQL function or
** aggregate may take any number of arguments between 0 and the limit
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
** parameter is less than -1 or greater than 127 then the behavior is
** undefined.
**
** The fourth parameter, eTextRep, specifies what
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
** its parameters.  Any SQL function implementation should be able to work
** work with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
** more efficient with one encoding than another.  It is allowed to
** invoke sqlite3_create_function() or sqlite3_create_function16() multiple

**
** An application-defined function is permitted to call other
** SQLite interfaces.  However, such calls must not
** close the database connection nor finalize or reset the prepared
** statement in which the function is running.
**
** Requirements:
** [H16103] [H16106] [H16109] [H16112] [H16118] [H16121] [H16127]
** [H16130] [H16133] [H16136] [H16139] [H16142]
*/
int sqlite3_create_function(
  sqlite3 *db,
  const char *zFunctionName,
  int nArg,
  int eTextRep,