NAME

luaL_checkoption — checks whether the function argument is a string, function indicator [-0, +0, v]

SYNOPSIS

#include <lauxlib.h>

int
luaL_checkoption(lua_State *L, int narg, const char *def, const char *const lst[]);

DESCRIPTION

luaL_checkoption() checks whether the function argument narg is a string and searches for this string in the array lst (which must be NULL -terminated). Returns the index in the array where the string was found. Raises an error if the argument is not a string or if the string cannot be found.

If def is not NULL, the function uses def as a default value when there is no argument narg or if this argument is nil.

This is a useful function for mapping strings to C enums. (The usual convention in Lua libraries is to use strings instead of numbers to select options.)

SEE ALSO

Roberto Ierusalimschy, Luiz Henrique de Figueiredo, and Waldemar Celes, Lua 5.1 Reference Manual.

HISTORY

The luaL_checkoption() manual page is based on Lua Reference Manual 5.1 and was created by Sergey Bronnikov.