D1: Out of memory problems

[Kagamin via Digitalmars-d-learn]

Parsers unique duplicated strings via a name table:
string udup(string s, ref string[string] nameTable)
{
   if(s in nameTable)return nameTable[s];
   string s1=s.dup;
   nameTable[s1]=s1;
   return s1;
}

This way you avoid extra duplicates. You can also try to free 
file content manually when it's processed.