Example of reading exported functions from a DLL using Ward's winim/memlib library.

dllExports.nim

import winim, strformat

proc `[]`[T](x: T, U: typedesc): U =
  cast[U](x)

proc `{}`[T](x: T, U: typedesc): U =
  when sizeof(x) == 1: x[uint8][U]
  elif sizeof(x) == 2: x[uint16][U]
  elif sizeof(x) == 4: x[uint32][U]
  elif sizeof(x) == 8: x[uint64][U]
  else: {.fatal.}

template `{}`[T](p: T, x: SomeInteger): T =
  cast[T]((cast[int](p) +% x{int}))

template `++`[T](p: var ptr T) =
  p = cast[ptr T](p[int] +% sizeof(T))

let
  dllBase = LoadLibraryA("ntdll")
  dosHeader = cast[PIMAGE_DOS_HEADER](dllBase)
  imageNTHeaders = cast[PIMAGE_NT_HEADERS](cast[DWORD_PTR](dllBase) + dosHeader.e_lfanew)
  exportDirectoryRVA = cast[DWORD](imageNTHeaders.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress)
  imageExportDirectory = cast[PIMAGE_EXPORT_DIRECTORY](cast[DWORD_PTR](dllBase) + exportDirectoryRVA)

var 
  nameRef = cast[pointer](dllBase){imageExportDirectory.AddressOfNames}[ptr uint32]
  ordinal = cast[pointer](dllBase){imageExportDirectory.AddressOfNameOrdinals}[ptr uint16]

for i in 0 ..< imageExportDirectory.NumberOfNames:
  let
    name = cast[pointer](dllBase){nameRef[]}[cstring]
    index = int ordinal[]
  
  echo name
  echo index

  ++nameRef
  ++ordinal