// t3(condition, statement, index)
static Triple<LS, LS, Int> tok_parseIfStatement(L<S> tok) {
  if (!eqGet(tok, 1, "if") || !eqGet(tok, 3, "(")) null;
  int clBr = findEndOfBracketPart(tok, 5)-1;
  int end = tok_findEndOfStatement(tok, clBr+2);
  ret t3(subList(tok, 6, clBr), subList(tok, clBr+1, end+1), end+1);
}