fix fileExists ambiguity for Nim < 1.4 & bump version

nimcuda.nimble

@@ -1,6 +1,6 @@
 # Package
 
-version       = "0.1.8"
+version       = "0.1.9"
 author        = "Andrea Ferretti"
 description   = "Nim binding for CUDA"
 license       = "Apache2"
@@ -12,6 +12,12 @@ requires "nim >= 0.16.0"
 
 import os, strutils
 
+proc fExists(f: string): bool =
+  when (NimMajor, NimMinor) < (1, 4):
+    result = os.fileExists(f)
+  else:
+    result = fileExists(f)
+
 proc patch(libName: string): string =
   when defined(windows):
     let libpath = getEnv("CUDA_PATH") / "include" / libName
@@ -23,7 +29,7 @@ proc patch(libName: string): string =
     patchPath = "c2nim" / libName
     outPath = "headers" / libName
     libContent =
-      if fileExists(simpleLibPath): readFile(simpleLibPath)
+      if fExists(simpleLibPath): readFile(simpleLibPath)
       else: readFile(libPath) #.replace("#if defined(__cplusplus)", "#ifdef __cplusplus")
     patchContent = readFile(patchPath)
   writeFile(outPath, patchContent & libContent)