Reduce scope of for loop variables to for loop initializer (#517)

hal/include/HAL/handles/LimitedClassedHandleResource.h

@@ -58,8 +58,7 @@ LimitedClassedHandleResource<THandle, TStruct, size, enumValue>::Allocate(
     std::shared_ptr<TStruct> toSet) {
   // globally lock to loop through indices
   std::lock_guard<priority_mutex> sync(m_allocateMutex);
-  int16_t i;
-  for (i = 0; i < size; i++) {
+  for (int16_t i = 0; i < size; i++) {
     if (m_structures[i] == nullptr) {
       // if a false index is found, grab its specific mutex
       // and allocate it.

hal/include/HAL/handles/LimitedHandleResource.h

@@ -54,8 +54,7 @@ template <typename THandle, typename TStruct, int16_t size,
 THandle LimitedHandleResource<THandle, TStruct, size, enumValue>::Allocate() {
   // globally lock to loop through indices
   std::lock_guard<priority_mutex> sync(m_allocateMutex);
-  int16_t i;
-  for (i = 0; i < size; i++) {
+  for (int16_t i = 0; i < size; i++) {
     if (m_structures[i] == nullptr) {
       // if a false index is found, grab its specific mutex
       // and allocate it.

wpilibc/athena/src/RobotDrive.cpp

@@ -640,13 +640,12 @@ double RobotDrive::Limit(double num) {
  */
 void RobotDrive::Normalize(double* wheelSpeeds) {
   double maxMagnitude = std::fabs(wheelSpeeds[0]);
-  int i;
-  for (i = 1; i < kMaxNumberOfMotors; i++) {
+  for (int i = 1; i < kMaxNumberOfMotors; i++) {
     double temp = std::fabs(wheelSpeeds[i]);
     if (maxMagnitude < temp) maxMagnitude = temp;
   }
   if (maxMagnitude > 1.0) {
-    for (i = 0; i < kMaxNumberOfMotors; i++) {
+    for (int i = 0; i < kMaxNumberOfMotors; i++) {
       wheelSpeeds[i] = wheelSpeeds[i] / maxMagnitude;
     }
   }

wpilibc/shared/src/Commands/CommandGroup.cpp

@@ -43,8 +43,8 @@ void CommandGroup::AddSequential(Command* command) {
   // Iterate through command->GetRequirements() and call Requires() on each
   // required subsystem
   Command::SubsystemSet requirements = command->GetRequirements();
-  auto iter = requirements.begin();
-  for (; iter != requirements.end(); iter++) Requires(*iter);
+  for (auto iter = requirements.begin(); iter != requirements.end(); iter++)
+    Requires(*iter);
 }
 
 /**
@@ -83,8 +83,8 @@ void CommandGroup::AddSequential(Command* command, double timeout) {
   // Iterate through command->GetRequirements() and call Requires() on each
   // required subsystem
   Command::SubsystemSet requirements = command->GetRequirements();
-  auto iter = requirements.begin();
-  for (; iter != requirements.end(); iter++) Requires(*iter);
+  for (auto iter = requirements.begin(); iter != requirements.end(); iter++)
+    Requires(*iter);
 }
 
 /**
@@ -120,8 +120,8 @@ void CommandGroup::AddParallel(Command* command) {
   // Iterate through command->GetRequirements() and call Requires() on each
   // required subsystem
   Command::SubsystemSet requirements = command->GetRequirements();
-  auto iter = requirements.begin();
-  for (; iter != requirements.end(); iter++) Requires(*iter);
+  for (auto iter = requirements.begin(); iter != requirements.end(); iter++)
+    Requires(*iter);
 }
 
 /**
@@ -168,8 +168,8 @@ void CommandGroup::AddParallel(Command* command, double timeout) {
   // Iterate through command->GetRequirements() and call Requires() on each
   // required subsystem
   Command::SubsystemSet requirements = command->GetRequirements();
-  auto iter = requirements.begin();
-  for (; iter != requirements.end(); iter++) Requires(*iter);
+  for (auto iter = requirements.begin(); iter != requirements.end(); iter++)
+    Requires(*iter);
 }
 
 void CommandGroup::_Initialize() { m_currentCommandIndex = -1; }
@@ -227,8 +227,7 @@ void CommandGroup::_Execute() {
   }
 
   // Run Children
-  auto iter = m_children.begin();
-  for (; iter != m_children.end();) {
+  for (auto iter = m_children.begin(); iter != m_children.end();) {
     entry = *iter;
     Command* child = entry.m_command;
     if (entry.IsTimedOut()) child->_Cancel();
@@ -252,8 +251,7 @@ void CommandGroup::_End() {
     cmd->Removed();
   }
 
-  auto iter = m_children.begin();
-  for (; iter != m_children.end(); iter++) {
+  for (auto iter = m_children.begin(); iter != m_children.end(); iter++) {
     Command* cmd = iter->m_command;
     cmd->_Cancel();
     cmd->Removed();
@@ -289,8 +287,7 @@ bool CommandGroup::IsInterruptible() const {
     if (!cmd->IsInterruptible()) return false;
   }
 
-  auto iter = m_children.cbegin();
-  for (; iter != m_children.cend(); iter++) {
+  for (auto iter = m_children.cbegin(); iter != m_children.cend(); iter++) {
     if (!iter->m_command->IsInterruptible()) return false;
   }
 
@@ -298,14 +295,13 @@ bool CommandGroup::IsInterruptible() const {
 }
 
 void CommandGroup::CancelConflicts(Command* command) {
-  auto childIter = m_children.begin();
-  for (; childIter != m_children.end();) {
+  for (auto childIter = m_children.begin(); childIter != m_children.end();) {
     Command* child = childIter->m_command;
     bool erased = false;
 
     Command::SubsystemSet requirements = command->GetRequirements();
-    auto requirementIter = requirements.begin();
-    for (; requirementIter != requirements.end(); requirementIter++) {
+    for (auto requirementIter = requirements.begin();
+         requirementIter != requirements.end(); requirementIter++) {
       if (child->DoesRequire(*requirementIter)) {
         child->_Cancel();
         child->Removed();

wpilibc/shared/src/Commands/Scheduler.cpp

@@ -68,8 +68,8 @@ void Scheduler::ProcessCommandAddition(Command* command) {
   if (found == m_commands.end()) {
     // Check that the requirements can be had
     Command::SubsystemSet requirements = command->GetRequirements();
-    Command::SubsystemSet::iterator iter;
-    for (iter = requirements.begin(); iter != requirements.end(); iter++) {
+    for (Command::SubsystemSet::iterator iter = requirements.begin();
+         iter != requirements.end(); iter++) {
       Subsystem* lock = *iter;
       if (lock->GetCurrentCommand() != nullptr &&
           !lock->GetCurrentCommand()->IsInterruptible())
@@ -78,7 +78,8 @@ void Scheduler::ProcessCommandAddition(Command* command) {
 
     // Give it the requirements
     m_adding = true;
-    for (iter = requirements.begin(); iter != requirements.end(); iter++) {
+    for (Command::SubsystemSet::iterator iter = requirements.begin();
+         iter != requirements.end(); iter++) {
       Subsystem* lock = *iter;
       if (lock->GetCurrentCommand() != nullptr) {
         lock->GetCurrentCommand()->Cancel();
@@ -115,8 +116,8 @@ void Scheduler::Run() {
     if (!m_enabled) return;
 
     std::lock_guard<priority_mutex> sync(m_buttonsLock);
-    auto rButtonIter = m_buttons.rbegin();
-    for (; rButtonIter != m_buttons.rend(); rButtonIter++) {
+    for (auto rButtonIter = m_buttons.rbegin(); rButtonIter != m_buttons.rend();
+         rButtonIter++) {
       (*rButtonIter)->Execute();
     }
   }
@@ -124,11 +125,11 @@ void Scheduler::Run() {
   m_runningCommandsChanged = false;
 
   // Loop through the commands
-  auto commandIter = m_commands.begin();
-  for (; commandIter != m_commands.end();) {
+  for (auto commandIter = m_commands.begin();
+       commandIter != m_commands.end();) {
     Command* command = *commandIter;
     // Increment before potentially removing to keep the iterator valid
-    commandIter++;
+    ++commandIter;
     if (!command->Run()) {
       Remove(command);
       m_runningCommandsChanged = true;
@@ -138,16 +139,16 @@ void Scheduler::Run() {
   // Add the new things
   {
     std::lock_guard<priority_mutex> sync(m_additionsLock);
-    auto additionsIter = m_additions.begin();
-    for (; additionsIter != m_additions.end(); additionsIter++) {
+    for (auto additionsIter = m_additions.begin();
+         additionsIter != m_additions.end(); additionsIter++) {
       ProcessCommandAddition(*additionsIter);
     }
     m_additions.clear();
   }
 
   // Add in the defaults
-  auto subsystemIter = m_subsystems.begin();
-  for (; subsystemIter != m_subsystems.end(); subsystemIter++) {
+  for (auto subsystemIter = m_subsystems.begin();
+       subsystemIter != m_subsystems.end(); subsystemIter++) {
     Subsystem* lock = *subsystemIter;
     if (lock->GetCurrentCommand() == nullptr) {
       ProcessCommandAddition(lock->GetDefaultCommand());
@@ -188,8 +189,7 @@ void Scheduler::Remove(Command* command) {
   if (!m_commands.erase(command)) return;
 
   Command::SubsystemSet requirements = command->GetRequirements();
-  auto iter = requirements.begin();
-  for (; iter != requirements.end(); iter++) {
+  for (auto iter = requirements.begin(); iter != requirements.end(); iter++) {
     Subsystem* lock = *iter;
     lock->SetCurrentCommand(nullptr);
   }
@@ -220,7 +220,6 @@ void Scheduler::ResetAll() {
  * SmartDashboard.
  */
 void Scheduler::UpdateTable() {
-  CommandSet::iterator commandIter;
   if (m_table != nullptr) {
     // Get the list of possible commands to cancel
     auto new_toCancel = m_table->GetValue("Cancel");
@@ -233,8 +232,8 @@ void Scheduler::UpdateTable() {
     // cancel commands that have had the cancel buttons pressed
     // on the SmartDashboad
     if (!toCancel.empty()) {
-      for (commandIter = m_commands.begin(); commandIter != m_commands.end();
-           ++commandIter) {
+      for (auto commandIter = m_commands.begin();
+           commandIter != m_commands.end(); ++commandIter) {
         for (size_t i = 0; i < toCancel.size(); i++) {
           Command* c = *commandIter;
           if (c->GetID() == toCancel[i]) {
@@ -250,8 +249,8 @@ void Scheduler::UpdateTable() {
     if (m_runningCommandsChanged) {
       commands.resize(0);
       ids.resize(0);
-      for (commandIter = m_commands.begin(); commandIter != m_commands.end();
-           ++commandIter) {
+      for (auto commandIter = m_commands.begin();
+           commandIter != m_commands.end(); ++commandIter) {
         Command* c = *commandIter;
         commands.push_back(c->GetName());
         ids.push_back(c->GetID());

wpilibc/shared/src/Commands/Subsystem.cpp

@@ -49,8 +49,7 @@ void Subsystem::SetDefaultCommand(Command* command) {
   } else {
     bool found = false;
     Command::SubsystemSet requirements = command->GetRequirements();
-    auto iter = requirements.begin();
-    for (; iter != requirements.end(); iter++) {
+    for (auto iter = requirements.begin(); iter != requirements.end(); iter++) {
       if (*iter == this) {
         found = true;
         break;

wpilibc/sim/src/DriverStation.cpp

@@ -134,11 +134,12 @@ int16_t DriverStation::GetStickButtons(int stick) {
                                "stick must be between 0 and 5");
     return false;
   }
-  int16_t btns = 0, btnid;
+  int16_t btns = 0;
 
   std::unique_lock<std::recursive_mutex> lock(m_joystickMutex);
   gazebo::msgs::FRCJoystickPtr joy = joysticks[stick];
-  for (btnid = 0; btnid < joy->buttons().size() && btnid < 12; btnid++) {
+  for (int16_t btnid = 0; btnid < joy->buttons().size() && btnid < 12;
+       btnid++) {
     if (joysticks[stick]->buttons(btnid)) {
       btns |= (1 << btnid);
     }

wpilibc/sim/src/RobotDrive.cpp

@@ -633,13 +633,12 @@ double RobotDrive::Limit(double num) {
  */
 void RobotDrive::Normalize(double* wheelSpeeds) {
   double maxMagnitude = std::fabs(wheelSpeeds[0]);
-  int i;
-  for (i = 1; i < kMaxNumberOfMotors; i++) {
+  for (int i = 1; i < kMaxNumberOfMotors; i++) {
     double temp = std::fabs(wheelSpeeds[i]);
     if (maxMagnitude < temp) maxMagnitude = temp;
   }
   if (maxMagnitude > 1.0) {
-    for (i = 0; i < kMaxNumberOfMotors; i++) {
+    for (int i = 0; i < kMaxNumberOfMotors; i++) {
       wheelSpeeds[i] = wheelSpeeds[i] / maxMagnitude;
     }
   }