[commands] Mark CommandPtr class as [[nodiscard]] (#7803)

This has the same effect but makes it so any user code returning CommandPtr can't discard a returned command.

Signed-off-by: Eric Ward <ezeward4@gmail.com>

wpilibNewCommands/src/main/native/include/frc2/command/Command.h

@@ -192,7 +192,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param duration the timeout duration
    * @return the command with the timeout added
    */
-  [[nodiscard]]
   CommandPtr WithTimeout(units::second_t duration) &&;
 
   /**
@@ -203,7 +202,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param condition the interrupt condition
    * @return the command with the interrupt condition added
    */
-  [[nodiscard]]
   CommandPtr Until(std::function<bool()> condition) &&;
 
   /**
@@ -214,7 +212,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param condition the run condition
    * @return the command with the run condition added
    */
-  [[nodiscard]]
   CommandPtr OnlyWhile(std::function<bool()> condition) &&;
 
   /**
@@ -224,7 +221,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param requirements the required subsystems
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr BeforeStarting(std::function<void()> toRun,
                             Requirements requirements = {}) &&;
 
@@ -235,7 +231,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param before the command to run before this one
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr BeforeStarting(CommandPtr&& before) &&;
 
   /**
@@ -245,7 +240,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param requirements the required subsystems
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr AndThen(std::function<void()> toRun,
                      Requirements requirements = {}) &&;
 
@@ -257,7 +251,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param next the commands to run next
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr AndThen(CommandPtr&& next) &&;
 
   /**
@@ -266,7 +259,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    *
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr Repeatedly() &&;
 
   /**
@@ -282,7 +274,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @return the decorated command
    * @see ProxyCommand
    */
-  [[nodiscard]]
   CommandPtr AsProxy() &&;
 
   /**
@@ -294,7 +285,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param condition the condition that will prevent the command from running
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr Unless(std::function<bool()> condition) &&;
 
   /**
@@ -306,7 +296,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param condition the condition that will allow the command to run
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr OnlyIf(std::function<bool()> condition) &&;
 
   /**
@@ -330,7 +319,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @return the decorated command
    * @see WithDeadline
    */
-  [[nodiscard]]
   CommandPtr DeadlineFor(CommandPtr&& parallel) &&;
 
   /**
@@ -341,7 +329,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param parallel the commands to run in parallel
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr AlongWith(CommandPtr&& parallel) &&;
 
   /**
@@ -352,7 +339,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param parallel the commands to run in parallel
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr RaceWith(CommandPtr&& parallel) &&;
 
   /**
@@ -361,7 +347,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param doesRunWhenDisabled true to run when disabled.
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr IgnoringDisable(bool doesRunWhenDisabled) &&;
 
   /**
@@ -370,7 +355,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param interruptBehavior the desired interrupt behavior
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr WithInterruptBehavior(
       Command::InterruptionBehavior interruptBehavior) &&;
 
@@ -382,7 +366,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * command was interrupted.
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr FinallyDo(std::function<void(bool)> end) &&;
 
   /**
@@ -394,7 +377,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * interrupted.
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr FinallyDo(std::function<void()> end) &&;
 
   /**
@@ -404,7 +386,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param handler a lambda to run when the command is interrupted
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr HandleInterrupt(std::function<void()> handler) &&;
 
   /**
@@ -413,7 +394,6 @@ class Command : public wpi::Sendable, public wpi::SendableHelper<Command> {
    * @param name name
    * @return the decorated Command
    */
-  [[nodiscard]]
   CommandPtr WithName(std::string_view name) &&;
 
   /**

wpilibNewCommands/src/main/native/include/frc2/command/CommandPtr.h

@@ -25,7 +25,8 @@ namespace frc2 {
  * std::unique_ptr<Command>, use CommandPtr::Unwrap to convert.
  * CommandPtr::UnwrapVector does the same for vectors.
  */
-class CommandPtr final {
+class [[nodiscard]]
+CommandPtr final {
  public:
   explicit CommandPtr(std::unique_ptr<Command>&& command);
 
@@ -46,7 +47,6 @@ class CommandPtr final {
    *
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr Repeatedly() &&;
 
   /**
@@ -60,7 +60,6 @@ class CommandPtr final {
    * @return the decorated command
    * @see ProxyCommand
    */
-  [[nodiscard]]
   CommandPtr AsProxy() &&;
 
   /**
@@ -69,7 +68,6 @@ class CommandPtr final {
    * @param doesRunWhenDisabled true to run when disabled
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr IgnoringDisable(bool doesRunWhenDisabled) &&;
 
   /**
@@ -78,7 +76,6 @@ class CommandPtr final {
    * @param interruptBehavior the desired interrupt behavior
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr WithInterruptBehavior(
       Command::InterruptionBehavior interruptBehavior) &&;
 
@@ -89,7 +86,6 @@ class CommandPtr final {
    * @param requirements the required subsystems
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr AndThen(std::function<void()> toRun,
                      Requirements requirements = {}) &&;
 
@@ -101,7 +97,6 @@ class CommandPtr final {
    * @param next the commands to run next
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr AndThen(CommandPtr&& next) &&;
 
   /**
@@ -111,7 +106,6 @@ class CommandPtr final {
    * @param requirements the required subsystems
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr BeforeStarting(std::function<void()> toRun,
                             Requirements requirements = {}) &&;
 
@@ -122,7 +116,6 @@ class CommandPtr final {
    * @param before the command to run before this one
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr BeforeStarting(CommandPtr&& before) &&;
 
   /**
@@ -133,7 +126,6 @@ class CommandPtr final {
    * @param duration the timeout duration
    * @return the command with the timeout added
    */
-  [[nodiscard]]
   CommandPtr WithTimeout(units::second_t duration) &&;
 
   /**
@@ -144,7 +136,6 @@ class CommandPtr final {
    * @param condition the interrupt condition
    * @return the command with the interrupt condition added
    */
-  [[nodiscard]]
   CommandPtr Until(std::function<bool()> condition) &&;
 
   /**
@@ -155,7 +146,6 @@ class CommandPtr final {
    * @param condition the run condition
    * @return the command with the run condition added
    */
-  [[nodiscard]]
   CommandPtr OnlyWhile(std::function<bool()> condition) &&;
 
   /**
@@ -167,7 +157,6 @@ class CommandPtr final {
    * @param condition the condition that will prevent the command from running
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr Unless(std::function<bool()> condition) &&;
 
   /**
@@ -179,7 +168,6 @@ class CommandPtr final {
    * @param condition the condition that will allow the command to run
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr OnlyIf(std::function<bool()> condition) &&;
 
   /**
@@ -201,7 +189,7 @@ class CommandPtr final {
    * @param parallel the commands to run in parallel
    * @return the decorated command
    */
-  [[nodiscard]] [[deprecated("Replace with DeadlineFor")]]
+  [[deprecated("Replace with DeadlineFor")]]
   CommandPtr DeadlineWith(CommandPtr&& parallel) &&;
 
   /**
@@ -214,7 +202,6 @@ class CommandPtr final {
    * will be interupted when the deadline command ends
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr DeadlineFor(CommandPtr&& parallel) &&;
   /**
    * Decorates this command with a set of commands to run parallel to it, ending
@@ -224,7 +211,6 @@ class CommandPtr final {
    * @param parallel the commands to run in parallel
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr AlongWith(CommandPtr&& parallel) &&;
 
   /**
@@ -235,7 +221,6 @@ class CommandPtr final {
    * @param parallel the commands to run in parallel
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr RaceWith(CommandPtr&& parallel) &&;
 
   /**
@@ -246,7 +231,6 @@ class CommandPtr final {
    * command was interrupted
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr FinallyDo(std::function<void(bool)> end) &&;
 
   /**
@@ -258,7 +242,6 @@ class CommandPtr final {
    * interrupted.
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr FinallyDo(std::function<void()> end) &&;
 
   /**
@@ -268,7 +251,6 @@ class CommandPtr final {
    * @param handler a lambda to run when the command is interrupted
    * @return the decorated command
    */
-  [[nodiscard]]
   CommandPtr HandleInterrupt(std::function<void()> handler) &&;
 
   /**
@@ -278,7 +260,6 @@ class CommandPtr final {
    * @param name name
    * @return the decorated Command
    */
-  [[nodiscard]]
   CommandPtr WithName(std::string_view name) &&;
 
   /**

wpilibNewCommands/src/main/native/include/frc2/command/Commands.h

@@ -29,7 +29,6 @@ namespace cmd {
 /**
  * Constructs a command that does nothing, finishing immediately.
  */
-[[nodiscard]]
 CommandPtr None();
 
 /**
@@ -38,7 +37,6 @@ CommandPtr None();
  * @param requirements Subsystems to require
  * @return the command
  */
-[[nodiscard]]
 CommandPtr Idle(Requirements requirements = {});
 
 // Action Commands
@@ -49,7 +47,6 @@ CommandPtr Idle(Requirements requirements = {});
  * @param action the action to run
  * @param requirements subsystems the action requires
  */
-[[nodiscard]]
 CommandPtr RunOnce(std::function<void()> action,
                    Requirements requirements = {});
 
@@ -59,7 +56,6 @@ CommandPtr RunOnce(std::function<void()> action,
  * @param action the action to run
  * @param requirements subsystems the action requires
  */
-[[nodiscard]]
 CommandPtr Run(std::function<void()> action, Requirements requirements = {});
 
 /**
@@ -70,7 +66,6 @@ CommandPtr Run(std::function<void()> action, Requirements requirements = {});
  * @param end the action to run on interrupt
  * @param requirements subsystems the action requires
  */
-[[nodiscard]]
 CommandPtr StartEnd(std::function<void()> start, std::function<void()> end,
                     Requirements requirements = {});
 
@@ -82,7 +77,6 @@ CommandPtr StartEnd(std::function<void()> start, std::function<void()> end,
  * @param end the action to run on interrupt
  * @param requirements subsystems the action requires
  */
-[[nodiscard]]
 CommandPtr RunEnd(std::function<void()> run, std::function<void()> end,
                   Requirements requirements = {});
 
@@ -94,7 +88,6 @@ CommandPtr RunEnd(std::function<void()> run, std::function<void()> end,
  * @param run the action to run every iteration
  * @param requirements subsystems the action requires
  */
-[[nodiscard]]
 CommandPtr StartRun(std::function<void()> start, std::function<void()> run,
                     Requirements requirements = {});
 
@@ -103,7 +96,6 @@ CommandPtr StartRun(std::function<void()> start, std::function<void()> run,
  *
  * @param msg the message to print
  */
-[[nodiscard]]
 CommandPtr Print(std::string_view msg);
 
 // Idling Commands
@@ -113,7 +105,6 @@ CommandPtr Print(std::string_view msg);
  *
  * @param duration after how long the command finishes
  */
-[[nodiscard]]
 CommandPtr Wait(units::second_t duration);
 
 /**
@@ -122,7 +113,6 @@ CommandPtr Wait(units::second_t duration);
  *
  * @param condition the condition
  */
-[[nodiscard]]
 CommandPtr WaitUntil(std::function<bool()> condition);
 
 // Selector Commands
@@ -134,7 +124,6 @@ CommandPtr WaitUntil(std::function<bool()> condition);
  * @param onFalse the command to run if the selector function returns false
  * @param selector the selector function
  */
-[[nodiscard]]
 CommandPtr Either(CommandPtr&& onTrue, CommandPtr&& onFalse,
                   std::function<bool()> selector);
 
@@ -145,7 +134,6 @@ CommandPtr Either(CommandPtr&& onTrue, CommandPtr&& onFalse,
  * @param commands map of commands to select from
  */
 template <typename Key, std::convertible_to<CommandPtr>... CommandPtrs>
-[[nodiscard]]
 CommandPtr Select(std::function<Key()> selector,
                   std::pair<Key, CommandPtrs>&&... commands) {
   std::vector<std::pair<Key, std::unique_ptr<Command>>> vec;
@@ -162,7 +150,6 @@ CommandPtr Select(std::function<Key()> selector,
  * @param supplier the command supplier
  * @param requirements the set of requirements for this command
  */
-[[nodiscard]]
 CommandPtr Defer(wpi::unique_function<CommandPtr()> supplier,
                  Requirements requirements);
 
@@ -173,7 +160,6 @@ CommandPtr Defer(wpi::unique_function<CommandPtr()> supplier,
  *
  * @param supplier the command supplier
  */
-[[nodiscard]]
 CommandPtr DeferredProxy(wpi::unique_function<Command*()> supplier);
 
 /**
@@ -183,7 +169,6 @@ CommandPtr DeferredProxy(wpi::unique_function<Command*()> supplier);
  *
  * @param supplier the command supplier
  */
-[[nodiscard]]
 CommandPtr DeferredProxy(wpi::unique_function<CommandPtr()> supplier);
 // Command Groups
 
@@ -205,14 +190,12 @@ std::vector<CommandPtr> MakeVector(Args&&... args) {
 /**
  * Runs a group of commands in series, one after the other.
  */
-[[nodiscard]]
 CommandPtr Sequence(std::vector<CommandPtr>&& commands);
 
 /**
  * Runs a group of commands in series, one after the other.
  */
 template <std::convertible_to<CommandPtr>... CommandPtrs>
-[[nodiscard]]
 CommandPtr Sequence(CommandPtrs&&... commands) {
   return Sequence(impl::MakeVector(std::forward<CommandPtrs>(commands)...));
 }
@@ -221,7 +204,6 @@ CommandPtr Sequence(CommandPtrs&&... commands) {
  * Runs a group of commands in series, one after the other. Once the last
  * command ends, the group is restarted.
  */
-[[nodiscard]]
 CommandPtr RepeatingSequence(std::vector<CommandPtr>&& commands);
 
 /**
@@ -229,7 +211,6 @@ CommandPtr RepeatingSequence(std::vector<CommandPtr>&& commands);
  * command ends, the group is restarted.
  */
 template <std::convertible_to<CommandPtr>... CommandPtrs>
-[[nodiscard]]
 CommandPtr RepeatingSequence(CommandPtrs&&... commands) {
   return RepeatingSequence(
       impl::MakeVector(std::forward<CommandPtrs>(commands)...));
@@ -239,7 +220,6 @@ CommandPtr RepeatingSequence(CommandPtrs&&... commands) {
  * Runs a group of commands at the same time. Ends once all commands in the
  * group finish.
  */
-[[nodiscard]]
 CommandPtr Parallel(std::vector<CommandPtr>&& commands);
 
 /**
@@ -247,7 +227,6 @@ CommandPtr Parallel(std::vector<CommandPtr>&& commands);
  * group finish.
  */
 template <std::convertible_to<CommandPtr>... CommandPtrs>
-[[nodiscard]]
 CommandPtr Parallel(CommandPtrs&&... commands) {
   return Parallel(impl::MakeVector(std::forward<CommandPtrs>(commands)...));
 }
@@ -256,7 +235,6 @@ CommandPtr Parallel(CommandPtrs&&... commands) {
  * Runs a group of commands at the same time. Ends once any command in the group
  * finishes, and cancels the others.
  */
-[[nodiscard]]
 CommandPtr Race(std::vector<CommandPtr>&& commands);
 
 /**
@@ -264,7 +242,6 @@ CommandPtr Race(std::vector<CommandPtr>&& commands);
  * finishes, and cancels the others.
  */
 template <std::convertible_to<CommandPtr>... CommandPtrs>
-[[nodiscard]]
 CommandPtr Race(CommandPtrs&&... commands) {
   return Race(impl::MakeVector(std::forward<CommandPtrs>(commands)...));
 }
@@ -273,7 +250,6 @@ CommandPtr Race(CommandPtrs&&... commands) {
  * Runs a group of commands at the same time. Ends once a specific command
  * finishes, and cancels the others.
  */
-[[nodiscard]]
 CommandPtr Deadline(CommandPtr&& deadline, std::vector<CommandPtr>&& others);
 
 /**
@@ -281,7 +257,6 @@ CommandPtr Deadline(CommandPtr&& deadline, std::vector<CommandPtr>&& others);
  * finishes, and cancels the others.
  */
 template <std::convertible_to<CommandPtr>... CommandPtrs>
-[[nodiscard]]
 CommandPtr Deadline(CommandPtr&& deadline, CommandPtrs&&... commands) {
   return Deadline(std::move(deadline),
                   impl::MakeVector(std::forward<CommandPtrs>(commands)...));

wpilibNewCommands/src/main/native/include/frc2/command/Subsystem.h

@@ -127,7 +127,6 @@ class Subsystem {
    *
    * @param action the action to run
    */
-  [[nodiscard]]
   CommandPtr RunOnce(std::function<void()> action);
 
   /**
@@ -136,7 +135,6 @@ class Subsystem {
    *
    * @param action the action to run
    */
-  [[nodiscard]]
   CommandPtr Run(std::function<void()> action);
 
   /**
@@ -146,7 +144,6 @@ class Subsystem {
    * @param start the action to run on start
    * @param end the action to run on interrupt
    */
-  [[nodiscard]]
   CommandPtr StartEnd(std::function<void()> start, std::function<void()> end);
 
   /**
@@ -156,7 +153,6 @@ class Subsystem {
    * @param run the action to run every iteration
    * @param end the action to run on interrupt
    */
-  [[nodiscard]]
   CommandPtr RunEnd(std::function<void()> run, std::function<void()> end);
 
   /**
@@ -166,7 +162,6 @@ class Subsystem {
    * @param start the action to run on start
    * @param run the action to run every iteration
    */
-  [[nodiscard]]
   CommandPtr StartRun(std::function<void()> start, std::function<void()> run);
 
   /**
@@ -176,7 +171,6 @@ class Subsystem {
    * @param supplier the command supplier.
    * @return the command.
    */
-  [[nodiscard]]
   CommandPtr Defer(wpi::unique_function<CommandPtr()> supplier);
 };
 }  // namespace frc2

wpilibNewCommands/src/test/native/cpp/frc2/command/CommandPtrTest.cpp

@@ -38,5 +38,6 @@ TEST_F(CommandPtrTest, MovedFrom) {
 }
 
 TEST_F(CommandPtrTest, NullInitialization) {
-  EXPECT_THROW(CommandPtr{std::unique_ptr<Command>{}}, frc::RuntimeError);
+  EXPECT_THROW(auto cmd = CommandPtr{std::unique_ptr<Command>{}},
+               frc::RuntimeError);
 }

wpilibcExamples/src/main/cpp/examples/DriveDistanceOffboard/include/subsystems/DriveSubsystem.h

@@ -82,7 +82,6 @@ class DriveSubsystem : public frc2::SubsystemBase {
    * @param distance The distance to drive forward.
    * @return A command.
    */
-  [[nodiscard]]
   frc2::CommandPtr ProfiledDriveDistance(units::meter_t distance);
 
   /**
@@ -92,7 +91,6 @@ class DriveSubsystem : public frc2::SubsystemBase {
    * @param distance The distance to drive forward.
    * @return A command.
    */
-  [[nodiscard]]
   frc2::CommandPtr DynamicProfiledDriveDistance(units::meter_t distance);
 
  private:

wpilibcExamples/src/main/cpp/examples/RapidReactCommandBot/include/subsystems/Drive.h

@@ -28,7 +28,6 @@ class Drive : public frc2::SubsystemBase {
    * @param fwd the commanded forward movement
    * @param rot the commanded rotation
    */
-  [[nodiscard]]
   frc2::CommandPtr ArcadeDriveCommand(std::function<double()> fwd,
                                       std::function<double()> rot);
 
@@ -39,7 +38,6 @@ class Drive : public frc2::SubsystemBase {
    * @param distance The distance to drive forward in meters
    * @param speed The fraction of max speed at which to drive
    */
-  [[nodiscard]]
   frc2::CommandPtr DriveDistanceCommand(units::meter_t distance, double speed);
 
   /**
@@ -48,7 +46,6 @@ class Drive : public frc2::SubsystemBase {
    *
    * @param angle The angle to turn to
    */
-  [[nodiscard]]
   frc2::CommandPtr TurnToAngleCommand(units::degree_t angle);
 
  private:

wpilibcExamples/src/main/cpp/examples/RapidReactCommandBot/include/subsystems/Intake.h

@@ -19,11 +19,9 @@ class Intake : public frc2::SubsystemBase {
 
   /** Returns a command that deploys the intake, and then runs the intake motor
    * indefinitely. */
-  [[nodiscard]]
   frc2::CommandPtr IntakeCommand();
 
   /** Returns a command that turns off and retracts the intake. */
-  [[nodiscard]]
   frc2::CommandPtr RetractCommand();
 
  private:

wpilibcExamples/src/main/cpp/examples/RapidReactCommandBot/include/subsystems/Pneumatics.h

@@ -17,7 +17,6 @@ class Pneumatics : frc2::SubsystemBase {
  public:
   Pneumatics();
   /** Returns a command that disables the compressor indefinitely. */
-  [[nodiscard]]
   frc2::CommandPtr DisableCompressorCommand();
 
   /**

wpilibcExamples/src/main/cpp/examples/RapidReactCommandBot/include/subsystems/Shooter.h

@@ -28,7 +28,6 @@ class Shooter : public frc2::SubsystemBase {
    *
    * @param setpointRotationsPerSecond The desired shooter velocity
    */
-  [[nodiscard]]
   frc2::CommandPtr ShootCommand(units::turns_per_second_t setpoint);
 
  private:

wpilibcExamples/src/main/cpp/examples/RapidReactCommandBot/include/subsystems/Storage.h

@@ -16,7 +16,6 @@ class Storage : frc2::SubsystemBase {
  public:
   Storage();
   /** Returns a command that runs the storage motor indefinitely. */
-  [[nodiscard]]
   frc2::CommandPtr RunCommand();
 
   /** Whether the ball storage is full. */