NULL

Description:

---

NULL is kinda like nil, but, nil is used for everything in Lua, meanwhile NULL is better to use only with CBaseEntity.

NULL in game code looks like this:

NULL = (CBaseEntity*)NULL
               

Why better use it only with entities

As writed above, NULL is just entity but invalid.
And for checking is entity valid you can just use NULL global.

For KeyValues you should use NULL_KEYVALUES.
For scripted vgui you should use INVALID_PANEL and for HFont class INVALID_FONT.

Returns:

---

1) NULL

Example:

---

if ToBaseEntity(pEntity) ~= NULL then
   print( "Entity is definetly valid." )
end
               

Or you can use this for preventing code from running if entity is not valid:

if ToBaseEntity(pEntity) == NULL then
   return
end