message: Special case for print
diff: @@ -33,6 +33,14 @@ function addType(env: TypeEnv, id: bril.Ident, type: bril.Type) {
  function checkInstr(
  env: TypeEnv, labels: Set<bril.Ident>, instr: bril.Instruction
  ) {
  + // Check for special cases.
  + if (instr.op === "print") {
  + if ('type' in instr) {
  + console.error(`print should have no result type`);
  + }
  + return;
  + }
  +
  // Do we know this operation?
  let opType = OP_TYPES[instr.op];
  if (!opType) {
  