//: Allow Mu programs to log facts just like we've been doing in C++ so far.

void test_trace() {
  run(
      "def main [\n"
      "  trace 1, [foo], [this is a trace in Mu]\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "foo: this is a trace in Mu\n"
  );
}

:(before "End Primitive Recipe Declarations")
TRACE,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "trace", TRACE);
:(before "End Primitive Recipe Checks")
case TRACE: {
  if (SIZE(inst.ingredients) < 3) {
    raise << maybe(get(Recipe, r).name) << "'trace' takes three or more ingredients rather than '" << to_original_string(inst) << "'\n" << end();
    break;
  }
  if (!is_mu_number(inst.ingredients.at(0))) {
    raise << maybe(get(Recipe, r).name) << "first ingredient of 'trace' should be a number (depth), but got '" << inst.ingredients.at(0).original_string << "'\n" << end();
    break;
  }
  if (!is_literal_text(inst.ingredients.at(1))) {
    raise << maybe(get(Recipe, r).name) << "second ingredient of 'trace' should be a literal string (label), but got '" << inst.ingredients.at(1).original_string << "'\n" << end();
    break;
  }
  break;
}
:(before "End Primitive Recipe Implementations")
case TRACE: {
  int depth = ingredients.at(0).at(0);
  string label = current_instruction().ingredients.at(1).name;
  ostringstream out;
  for (int i = 2;  i < SIZE(current_instruction().ingredients);  ++i) {
    if (i > 2) out << ' ';
    out << inspect(current_instruction().ingredients.at(i), ingredients.at(i));
  }
  trace(depth, label) << out.str() << end();
  break;
}

//: simpler limited version of 'trace'

:(before "End Types")  //: include in all cleaved compilation units
const int App_depth = 1;  // where all Mu code will trace to by default

:(before "End Primitive Recipe Declarations")
STASH,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "stash", STASH);
:(before "End Primitive Recipe Checks")
case STASH: {
  break;
}
:(before "End Primitive Recipe Implementations")
case STASH: {
  ostringstream out;
  for (int i = 0;  i < SIZE(current_instruction().ingredients);  ++i) {
    if (i) out << ' ';
    out << inspect(current_instruction().ingredients.at(i), ingredients.at(i));
  }
  trace(App_depth, "app") << out.str() << end();
  break;
}

:(code)
void test_stash_literal_string() {
  run(
      "def main [\n"
      "  stash [foo]\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "app: foo\n"
  );
}

void test_stash_literal_number() {
  run(
      "def main [\n"
      "  stash [foo:], 4\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "app: foo: 4\n"
  );
}

void test_stash_number() {
  run(
      "def main [\n"
      "  1:num <- copy 34\n"
      "  stash [foo:], 1:num\n"
      "]\n"
  );
  CHECK_TRACE_CONTENTS(
      "app: foo: 34\n"
  );
}

:(code)
string inspect(const reagent& r, const vector<double>& data) {
  if (is_literal(r))
    return r.name;
  // End inspect Special-cases(r, data)
  ostringstream out;
  for (long long i = 0;  i < SIZE(data);  ++i) {
    if (i) out << ' ';
    out << no_scientific(data.at(i));
  }
  return out.str();
}

:(before "End Primitive Recipe Declarations")
HIDE_ERRORS,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "hide-errors", HIDE_ERRORS);
:(before "End Primitive Recipe Checks")
case HIDE_ERRORS: {
  break;
}
:(before "End Primitive Recipe Implementations")
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