gistfile1.nim

{.experimental.}

type arrayUnchecked {.unchecked.} [T] = array[0..0, T]

type MatD[ElementT] = object
    n: int
    m: int
    data: ptr arrayUnchecked[ElementT]

template matD(nv,mv: int, elementT: typedesc = float64): expr =
    let size = nv*mv
    let memPtr = alloc0(nv*mv*sizeof(elementT))
    let arrayPtr = cast[ptr array[0..0, elementT]](memPtr)
    MatD[elementT](n: nv, m: mv, data: arrayPtr)

template `[]=`*[ElementT](mat: MatD[ElementT], index: int, value: expr) =
    mat.data[index] = value

template `[]`*[ElementT](mat: MatD[ElementT], index: int): expr =
    mat.data[index]

if true:
    var a = matD(4, 4)

    a[0] = 22
    echo a[0]