Squashed 'third_party/allwpilib_2017/' content from commit 35ac87d

Change-Id: I7bb6f5556c30d3f5a092e68de0be9c710c60c9f4
git-subtree-dir: third_party/allwpilib_2017
git-subtree-split: 35ac87d6ff8b7f061c4f18c9ea316e5dccd4888a
diff --git a/wpilibc/shared/include/Buttons/Trigger.h b/wpilibc/shared/include/Buttons/Trigger.h
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+++ b/wpilibc/shared/include/Buttons/Trigger.h
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+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2011-2017. All Rights Reserved.                        */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#pragma once
+
+#include <memory>
+#include <string>
+
+#include "SmartDashboard/Sendable.h"
+
+namespace frc {
+
+class Command;
+
+/**
+ * This class provides an easy way to link commands to inputs.
+ *
+ * It is very easy to link a polled input to a command.  For instance, you could
+ * link the trigger button of a joystick to a "score" command or an encoder
+ * reaching
+ * a particular value.
+ *
+ * It is encouraged that teams write a subclass of Trigger if they want to have
+ * something unusual (for instance, if they want to react to the user holding
+ * a button while the robot is reading a certain sensor input).  For this, they
+ * only have to write the {@link Trigger#Get()} method to get the full
+ * functionality
+ * of the Trigger class.
+ */
+class Trigger : public Sendable {
+ public:
+  Trigger() = default;
+  virtual ~Trigger() = default;
+  bool Grab();
+  virtual bool Get() = 0;
+  void WhenActive(Command* command);
+  void WhileActive(Command* command);
+  void WhenInactive(Command* command);
+  void CancelWhenActive(Command* command);
+  void ToggleWhenActive(Command* command);
+
+  void InitTable(std::shared_ptr<ITable> subtable) override;
+  std::shared_ptr<ITable> GetTable() const override;
+  std::string GetSmartDashboardType() const override;
+
+ protected:
+  std::shared_ptr<ITable> m_table;
+};
+
+}  // namespace frc