sbool loadLibraryOrSrcLib_srcLibsEnabled = true;

// to avoid checking src libs too often when booting OS
static ThreadLocal<Map<Long, File>> loadLibraryOrSrcLib_tempCache = new ThreadLocal;

static File loadLibraryOrSrcLib(S snippetID) ctex {
  long id = parseSnippetID(snippetID);
  
  if (loadLibraryOrSrcLib_tempCache! != null)
    try File f = loadLibraryOrSrcLib_tempCache->get(id);
  
  bool srcLib = loadLibraryOrSrcLib_srcLibsEnabled && isMarkedAsSrcLib(snippetID);
  if (srcLib) {
    File f = pairA(hotwire_compile(snippetID));
    mapPut(loadLibraryOrSrcLib_tempCache!, id, f);
  }
    
  File f = DiskSnippetCache_getLibrary(id);
  if (fileSize(f) != 0) ret f;
  try {
    ret loadDataSnippetToFile(snippetID);
  } catch e {
    if (loadLibraryOrSrcLib_srcLibsEnabled && nempty(loadSnippet(snippetID))) {
      markAsSrcLib(snippetID);
      ret pairA(hotwire_compile(snippetID));
    }
    throw rethrow(e);
  }
}