6 – The Standard Libraries

All libraries are implemented through the official C API and are provided as separate C modules. Unless otherwise noted, these library functions do not adjust its number of arguments to its expected parameters. For instance, a function documented as foo(arg) should not be called without an argument.

Currently, Lua has the following standard libraries:

• basic library (§6.1);
• coroutine library ();
• string manipulation (§6.4);
• basic UTF-8 support ();
• mathematical functions (§6.7) (sin, log, etc.);
• input and output ();
• debug facilities (§6.10).

To have access to these libraries, the C host program should call the function, which opens all standard libraries. Alternatively, the host program can open them individually by using luaL_requiref to call luaopen_base (for the basic library), luaopen_package (for the package library), luaopen_coroutine (for the coroutine library), luaopen_string (for the string library), (for the UTF-8 library), luaopen_table (for the table library), luaopen_math (for the mathematical library), luaopen_io (for the I/O library), luaopen_os (for the operating system library), and luaopen_debug (for the debug library). These functions are declared in .