Pointer math operations

Pointer objects supports as in C using some math operators to do calculations.
The result of an operation maybe another Pointer or an number for pointer substraction.

Pointer addition

You can add (+) a Lua integer to a Pointer, which will move the pointer forward by that number of elements.

Pointer substraction

You can substract (-) a Lua integer from a Pointer, which will move the pointer backward by that number of elements.

Subtracting one pointer from another is supported too, which gives the number of elements between them.

Warning

While pointer arithmetic can be powerful, it can also be a source of bugs if not handled carefully.
Keep attention to respect memory allocations and boundaries.

Example


--! luart-extensions
import c

-- Creates a Pointer from a C string
local c_ptr = c.Pointer(c.string("Hello LuaRT"))

-- Casts the pointer to a C string and adds 6 elements(chars), printing the resulting Pointer
print(c_ptr:as("char*") + 6)