svoid tok_replaceColonEqualsSyntax(LS tok) {
  int i;
  
  // "field := value" for defining fields e.g. in "uniq"
  while ((i = jfind_check(":", tok, "<id> :=")) >= 0) {
    tok.set(i, quote(tok.get(i)));
    tok.set(i+2, ",");
    tok.set(i+4, "");
    reTok(tok, i, i+5);
  }
  
  // "quoted" := value
  while ((i = jfind_check(":", tok, "<quoted> :=")) >= 0) {
    tok.set(i, tok.get(i));
    tok.set(i+2, ",");
    tok.set(i+4, "");
    reTok(tok, i, i+5);
  }
}