current line number in Lua

36
votes

Does Lua support something like C's __LINE__ macro, which returns the number of the current code line? I know Lua has a special built-in variable called _G, but I don't see line number in there...

1
lua

1 Answers

51
votes

From Lua using debug.getinfo, e.g.,

local line = debug.getinfo(1).currentline

From C using lua_getinfo (This will return the linenumber inside lua code)

  lua_Debug ar;
  lua_getstack(L, 1, &ar);
  lua_getinfo(L, "nSl", &ar);
  int line = ar.currentline

http://www.lua.org/manual/5.1/manual.html#lua_getinfo

http://www.lua.org/manual/5.1/manual.html#pdf-debug.getinfo