Style fixes

In particular, use std::make_shared and enumerate(). Also renamed some
fields to fit naming conventions.

src/libcmd/command.cc

@@ -121,25 +121,23 @@ ref<EvalState> EvalCommand::getEvalState()
  if (startReplOnEvalErrors)
  debuggerHook = [evalState{ref<EvalState>(evalState)}](const Error * error, const Env & env, const Expr & expr) {
  auto dts =
- error && expr.getPos() ?
- std::unique_ptr<DebugTraceStacker>(
- new DebugTraceStacker(
- *evalState,
- DebugTrace
- {.pos = (error->info().errPos ? *error->info().errPos : evalState->positions[expr.getPos()]),
- .expr = expr,
- .env = env,
- .hint = error->info().msg,
- .is_error = true
- }))
- : nullptr;
+ error && expr.getPos()
+ ? std::make_unique<DebugTraceStacker>(
+ *evalState,
+ DebugTrace {
+ .pos = error->info().errPos ? *error->info().errPos : evalState->positions[expr.getPos()],
+ .expr = expr,
+ .env = env,
+ .hint = error->info().msg,
+ .isError = true
+ })
+ : nullptr;
 
  if (error)
  printError("%s\n\n" ANSI_BOLD "Starting REPL to allow you to inspect the current state of the evaluator.\n" ANSI_NORMAL, error->what());
 
- if (expr.staticenv)
- {
- std::unique_ptr<valmap> vm(mapStaticEnvBindings(evalState->symbols, *expr.staticenv.get(), env));
+ if (expr.staticEnv) {
+ auto vm = mapStaticEnvBindings(evalState->symbols, *expr.staticEnv.get(), env);
  runRepl(evalState, expr, *vm);
  }
  };

src/libcmd/command.hh

@@ -275,6 +275,7 @@ void printClosureDiff(
 
 void runRepl(
  ref<EvalState> evalState,
- const Expr &expr,
+ const Expr & expr,
  const std::map<std::string, Value *> & extraEnv);
+
 }

src/libcmd/repl.cc

@@ -51,7 +51,7 @@ struct NixRepl
  ref<EvalState> state;
  Bindings * autoArgs;
 
- int debugTraceIndex;
+ size_t debugTraceIndex;
 
  Strings loadedFiles;
 
@@ -79,7 +79,7 @@ struct NixRepl
  void addVarToScope(const Symbol name, Value & v);
  Expr * parseString(std::string s);
  void evalString(std::string s, Value & v);
- void loadDebugTraceEnv(DebugTrace &dt);
+ void loadDebugTraceEnv(DebugTrace & dt);
 
  typedef std::set<Value *> ValuesSeen;
  std::ostream & printValue(std::ostream & str, Value & v, unsigned int maxDepth);
@@ -203,15 +203,16 @@ namespace {
  }
 }
 
-std::ostream& showDebugTrace(std::ostream &out, const PosTable &positions, const DebugTrace &dt)
+static std::ostream & showDebugTrace(std::ostream & out, const PosTable & positions, const DebugTrace & dt)
 {
- if (dt.is_error)
+ if (dt.isError)
  out << ANSI_RED "error: " << ANSI_NORMAL;
  out << dt.hint.str() << "\n";
 
  // prefer direct pos, but if noPos then try the expr.
- auto pos = (*dt.pos ? *dt.pos :
- positions[(dt.expr.getPos() ? dt.expr.getPos() : noPos)]);
+ auto pos = *dt.pos
+ ? *dt.pos
+ : positions[dt.expr.getPos() ? dt.expr.getPos() : noPos];
 
  if (pos) {
  printAtPos(pos, out);
@@ -258,8 +259,7 @@ void NixRepl::mainLoop(const std::vector<std::string> & files)
  while (true) {
  // When continuing input from previous lines, don't print a prompt, just align to the same
  // number of chars as the prompt.
- if (!getLine(input, input.empty() ? "nix-repl> " : " "))
- {
+ if (!getLine(input, input.empty() ? "nix-repl> " : " ")) {
  // ctrl-D should exit the debugger.
  state->debugStop = false;
  state->debugQuit = true;
@@ -279,8 +279,8 @@ void NixRepl::mainLoop(const std::vector<std::string> & files)
  // in debugger mode, an EvalError should trigger another repl session.
  // when that session returns the exception will land here. No need to show it again;
  // show the error for this repl session instead.
- if (debuggerHook && !this->state->debugTraces.empty())
- showDebugTrace(std::cout, this->state->positions, this->state->debugTraces.front());
+ if (debuggerHook && !state->debugTraces.empty())
+ showDebugTrace(std::cout, state->positions, state->debugTraces.front());
  else
  printMsg(lvlError, e.msg());
  } catch (Error & e) {
@@ -437,22 +437,16 @@ StorePath NixRepl::getDerivationPath(Value & v) {
  return *drvPath;
 }
 
-void NixRepl::loadDebugTraceEnv(DebugTrace &dt)
+void NixRepl::loadDebugTraceEnv(DebugTrace & dt)
 {
- if (dt.expr.staticenv)
- {
- initEnv();
+ initEnv();
 
- auto vm = std::make_unique<valmap>(*(mapStaticEnvBindings(this->state->symbols, *dt.expr.staticenv.get(), dt.env)));
+ if (dt.expr.staticEnv) {
+ auto vm = mapStaticEnvBindings(state->symbols, *dt.expr.staticEnv.get(), dt.env);
 
  // add staticenv vars.
- for (auto & [name, value] : *(vm.get())) {
- this->addVarToScope(this->state->symbols.create(name), *value);
- }
- }
- else
- {
- initEnv();
+ for (auto & [name, value] : *(vm.get()))
+ addVarToScope(state->symbols.create(name), *value);
  }
 }
 
@@ -509,45 +503,31 @@ bool NixRepl::processLine(std::string line)
 
  else if (command == ":d" || command == ":debug") {
  if (arg == "stack") {
- int idx = 0;
- for (auto iter = this->state->debugTraces.begin();
- iter != this->state->debugTraces.end();
- ++iter, ++idx) {
- std::cout << "\n" << ANSI_BLUE << idx << ANSI_NORMAL << ": ";
- showDebugTrace(std::cout, this->state->positions, *iter);
+ for (const auto & [idx, i] : enumerate(state->debugTraces)) {
+ std::cout << "\n" << ANSI_BLUE << idx << ANSI_NORMAL << ": ";
+ showDebugTrace(std::cout, state->positions, i);
  }
  } else if (arg == "env") {
- int idx = 0;
- for (auto iter = this->state->debugTraces.begin();
- iter != this->state->debugTraces.end();
- ++iter, ++idx) {
- if (idx == this->debugTraceIndex)
- {
- printEnvBindings(state->symbols,iter->expr, iter->env);
- break;
- }
+ for (const auto & [idx, i] : enumerate(state->debugTraces)) {
+ if (idx == debugTraceIndex) {
+ printEnvBindings(state->symbols, i.expr, i.env);
+ break;
+ }
  }
  }
- else if (arg.compare(0,4,"show") == 0) {
+ else if (arg.compare(0, 4, "show") == 0) {
  try {
  // change the DebugTrace index.
  debugTraceIndex = stoi(arg.substr(4));
- }
- catch (...)
- {
- }
+ } catch (...) { }
 
- int idx = 0;
- for (auto iter = this->state->debugTraces.begin();
- iter != this->state->debugTraces.end();
- ++iter, ++idx) {
- if (idx == this->debugTraceIndex)
- {
+ for (const auto & [idx, i] : enumerate(state->debugTraces)) {
+ if (idx == debugTraceIndex) {
  std::cout << "\n" << ANSI_BLUE << idx << ANSI_NORMAL << ": ";
- showDebugTrace(std::cout, this->state->positions, *iter);
+ showDebugTrace(std::cout, state->positions, i);
  std::cout << std::endl;
- printEnvBindings(state->symbols,iter->expr, iter->env);
- loadDebugTraceEnv(*iter);
+ printEnvBindings(state->symbols, i.expr, i.env);
+ loadDebugTraceEnv(i);
  break;
  }
  }
@@ -1032,9 +1012,8 @@ void runRepl(
  repl->initEnv();
 
  // add 'extra' vars.
- for (auto & [name, value] : extraEnv) {
+ for (auto & [name, value] : extraEnv)
  repl->addVarToScope(repl->state->symbols.create(name), *value);
- }
 
  repl->mainLoop({});
 }