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read in the arguments passed to a C function from Lua
#include <luasup/luasup.h>int slua_args_va( SLua_ErrFunc errfunc, const char *func, int n, va_list ap );
SLua_ErrFunc errfunc
- the error function
const char *func
- the name of the Lua called function. Used for error messages
int n
- the Lua argument position at which to start. Unary based.
va_list ap
- the list of arguments
This routine will read the arguments passed by Lua to a C function
when the function is called from Lua. It expects a va_list
of triples, each of which contains the argument's name (for error
reporting purposes), the argument's type (one of SLua_STRING
,
SLua_NUMBER
, or SLua_TABLE
) and a pointer to storage
for the argument. The list should be terminated by a NULL
value. Support is provided for optional arguements. These must be
at the end of the arguement list, and should have their type or'd
with SLua_OPTIONAL
(e.g. SLua_TABLE | SLua_OPTIONAL
).
To determine if an optional argument was present, use
slua_args_va
's return value.
Numeric values are stored as double
. String values are
returned as a pointer to a duplicate string. The calling routine is
responsible for deallocating this memory.
Arguments are returned beginning with the Lua argument at
the position specified by n
.
It returns the number of arguments found, or `-1' if an error ocurred.
Errors are returned via the passed SLua_ErrFunc
function.
Diab Jerius
/* --8<--8<--8<--8<-- * * Copyright (C) 2006 Smithsonian Astrophysical Observatory * * This file is part of luasup * * luasup is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * luasup is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the * Free Software Foundation, Inc. * 51 Franklin Street, Fifth Floor * Boston, MA 02110-1301, USA * * -->8-->8-->8-->8-- */ #include <stdarg.h> #include <luasup.h> int foo ( SLua_ErrFunc errfunc, char *func, ... ) { va_list ap; int n; va_start( ap, func ); n = slua_args_va( errfunc, func, 1, ap ); va_end( ap ); return n; }