svoid tok_for_unpair(LS tok) {

  jreplace(tok, "for (unpair <id> <id>, <id> :", "for (unpair $4 $5, $4 $7 :");

  jreplace(tok, "for (<id> <id>, <id> : unpair", "for (unpair $3 $4, $3 $6 :");

  jreplace(tok, "for (<id> <id>, <id> <id> : unpair", "for (unpair $3 $4, $6 $7 :");

  int i = -1;

  while ((i = jfind(tok, i+1, "for (unpair <id> <id>, <id> <id> :")) >= 0) {

    S type1 = tok.get(i+6), var1 = tok.get(i+8);

    S type2 = tok.get(i+12), var2 = tok.get(i+14);

    int iColon = indexOf(tok, ":", i);

    int iClosing = findEndOfBracketPart(tok, iColon)-1;

    int iCurly = iClosing+2;

    tok_statementToBlock(tok, iCurly);

    S pairVar = makeVar();

    replaceTokens(tok, i+4, iColon-1, tok_toNonPrimitiveTypes("Pair<" + type1 + ", " + type2 + ">") + " " + pairVar);

    tok.set(iCurly, "{ "

      + type1 + " " + var1 + " = pairA(" + pairVar + "); "

      + type2 + " " + var2 + " = pairB(" + pairVar + "); ");

    reTok(tok, i, iCurly+1);

  }

  // typeless version

  i = -1;

  while ((i = jfind(tok, i+1, "for (<id>, <id> : unpair")) >= 0) {

    S var1 = tok.get(i+4);

    S var2 = tok.get(i+8);

    int iColon = indexOf(tok, ":", i);

    int iClosing = findEndOfBracketPart(tok, iColon)-1;

    int iCurly = iClosing+2;

    tok_statementToBlock(tok, iCurly);

    S pairVar = makeVar();

    replaceTokens(tok, i+4, iColon+3, "var " + pairVar + ":");

    tok.set(iCurly, "{ "

      + "var " + var1 + " = pairA(" + pairVar + "); "

      + "var " + var2 + " = pairB(" + pairVar + "); ");

    reTok(tok, i, iCurly+1);

  }

}