tostring
Lua function

tostring

Summary

Converts its argument to a string

Prototype

s = tostring (a)


Description

Converts its argument to a string in a reasonable format. If a __tostring metatable field is found, that is used for the conversion.


print (tostring (print)) --> function: 0205A980
print (tostring (_G)) --> table: 02072780
print (tostring (1.23e10)) --> 12300000000

-- use __tostring to print a table

t = { age = 42, height = 102 }

setmetatable (t, 
  { 
  __tostring = function (t) 
    return "person of age " .. t.age
    end -- __tostring 
  }
 )

print (t) --> person of age 42


Also see bit.tostring which will convert a number to a string of any base in the range 2 to 36.

See Also ...

Topics

DOC_lua_base Lua base functions
DOC_lua_bc Lua bc (big number) functions
DOC_lua_bit Lua bit manipulation functions
DOC_lua_coroutines Lua coroutine functions
DOC_lua_debug Lua debug functions
DOC_lua_io Lua io functions
DOC_lua_math Lua math functions
DOC_lua_os Lua os functions
DOC_lua_package Lua package functions
DOC_lua_rex Lua PCRE regular expression functions
DOC_lua Lua script extensions
DOC_lua_string Lua string functions
DOC_lua_tables Lua table functions
DOC_lua_utils Lua utilities
DOC_scripting Scripting

Lua functions

LUA_assert assert (Asserts that condition is not nil and not false)
LUA_collectgarbage collectgarbage (Collects garbage)
LUA_dofile dofile (Executes a Lua file)
LUA_error error (Raises an error message)
LUA_gcinfo gcinfo (Returns amount of dynamic memory in use)
LUA_getfenv getfenv (Returns the current environment table)
LUA_getmetatable getmetatable (Returns the metatable for the object)
LUA_ipairs ipairs (Iterates over a numerically keyed table)
LUA_load load (Loads a chunk by calling a function repeatedly)
LUA_loadfile loadfile (Loads a Lua file and parses it)
LUA_loadlib loadlib (Loads a DLL (obsolete in Lua 5.1))
LUA_loadstring loadstring (Compiles a string of Lua code)
LUA_module module (Creates a Lua module)
LUA_next next (Returns next key / value pair in a table)
LUA_pairs pairs (Traverse all items in a table)
LUA_pcall pcall (Calls a function in protected mode)
LUA_print print (Prints its arguments)
LUA_rawequal rawequal (Compares two values for equality without invoking metamethods)
LUA_rawget rawget (Gets the value of a table item without invoking metamethods)
LUA_rawset rawset (Sets the value of a table item without invoking metamethods)
LUA_require require (Loads a module)
LUA_select select (Returns items in a list)
LUA_setfenv setfenv (Sets a function's environment)
LUA_setmetatable setmetatable (Sets the metatable for a table)
LUA_tonumber tonumber (Converts a string (of the given base) to a number)
LUA_type type (Returns the type of a variable)
LUA_unpack unpack (Unpacks a table into individual items)
LUA_xpcall xpcall (Calls a function with a custom error handler)

(Help topic: lua=tostring)

DOC_contents Documentation contents page