Add "operator bool" to SB APIs

Summary:
Our python version of the SB API has (the python equivalent of)
operator bool, but the C++ version doesn't.

This is because our python operators are added by modify-python-lldb.py,
which performs postprocessing on the swig-generated interface files.

In this patch, I add the "operator bool" to all SB classes which have an
IsValid method (which is the same logic used by modify-python-lldb.py).
This way, we make the two interfaces more constent, and it allows us to
rely on swig's automatic syntesis of python __nonzero__ methods instead
of doing manual fixups.

Reviewers: zturner, jingham, clayborg, jfb, serge-sans-paille

Subscribers: jdoerfert, lldb-commits

Differential Revision: https://reviews.llvm.org/D58792

llvm-svn: 355824

lldb/include/lldb/API/SBAddress.h

@@ -29,6 +29,8 @@ public:
 
   const lldb::SBAddress &operator=(const lldb::SBAddress &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBBlock.h

@@ -28,6 +28,8 @@ public:
 
   bool IsInlined() const;
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetInlinedName() const;

lldb/include/lldb/API/SBBreakpoint.h

@@ -36,6 +36,8 @@ public:
 
   break_id_t GetID() const;
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void ClearAllBreakpointSites();

lldb/include/lldb/API/SBBreakpointLocation.h

@@ -27,6 +27,8 @@ public:
 
   break_id_t GetID();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   lldb::SBAddress GetAddress();

lldb/include/lldb/API/SBBreakpointName.h

@@ -39,6 +39,8 @@ public:
 
   bool operator!=(const lldb::SBBreakpointName &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
   
   const char *GetName() const;

lldb/include/lldb/API/SBBroadcaster.h

@@ -25,6 +25,8 @@ public:
 
   ~SBBroadcaster();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBCommandInterpreter.h

@@ -87,6 +87,8 @@ public:
 
   static bool EventIsCommandInterpreterEvent(const lldb::SBEvent &event);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   bool CommandExists(const char *cmd);
@@ -272,6 +274,8 @@ class SBCommand {
 public:
   SBCommand();
 
+  explicit operator bool() const;
+
   bool IsValid();
 
   const char *GetName();

lldb/include/lldb/API/SBCommandReturnObject.h

@@ -32,6 +32,8 @@ public:
 
   lldb_private::CommandReturnObject *Release();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetOutput();

lldb/include/lldb/API/SBCommunication.h

@@ -37,6 +37,8 @@ public:
   SBCommunication(const char *broadcaster_name);
   ~SBCommunication();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   lldb::SBBroadcaster GetBroadcaster();

lldb/include/lldb/API/SBCompileUnit.h

@@ -24,6 +24,8 @@ public:
 
   const lldb::SBCompileUnit &operator=(const lldb::SBCompileUnit &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   lldb::SBFileSpec GetFileSpec() const;

lldb/include/lldb/API/SBData.h

@@ -29,6 +29,8 @@ public:
 
   void Clear();
 
+  explicit operator bool() const;
+
   bool IsValid();
 
   size_t GetByteSize();

lldb/include/lldb/API/SBDebugger.h

@@ -62,6 +62,8 @@ public:
 
   static void MemoryPressureDetected();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBDeclaration.h

@@ -25,6 +25,8 @@ public:
 
   const lldb::SBDeclaration &operator=(const lldb::SBDeclaration &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   lldb::SBFileSpec GetFileSpec() const;

lldb/include/lldb/API/SBError.h

@@ -46,6 +46,8 @@ public:
   int SetErrorStringWithFormat(const char *format, ...)
       __attribute__((format(printf, 2, 3)));
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   bool GetDescription(lldb::SBStream &description);

lldb/include/lldb/API/SBEvent.h

@@ -35,6 +35,8 @@ public:
 
   const SBEvent &operator=(const lldb::SBEvent &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetDataFlavor();

lldb/include/lldb/API/SBFileSpec.h

@@ -28,6 +28,8 @@ public:
 
   const SBFileSpec &operator=(const lldb::SBFileSpec &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   bool Exists() const;

lldb/include/lldb/API/SBFrame.h

@@ -26,6 +26,8 @@ public:
 
   bool IsEqual(const lldb::SBFrame &that) const;
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   uint32_t GetFrameID() const;

lldb/include/lldb/API/SBFunction.h

@@ -25,6 +25,8 @@ public:
 
   ~SBFunction();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetName() const;

lldb/include/lldb/API/SBInstruction.h

@@ -31,6 +31,8 @@ public:
 
   ~SBInstruction();
 
+  explicit operator bool() const;
+
   bool IsValid();
 
   SBAddress GetAddress();

lldb/include/lldb/API/SBInstructionList.h

@@ -25,6 +25,8 @@ public:
 
   ~SBInstructionList();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   size_t GetSize();

lldb/include/lldb/API/SBLineEntry.h

@@ -29,6 +29,8 @@ public:
 
   lldb::SBAddress GetEndAddress() const;
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   lldb::SBFileSpec GetFileSpec() const;

lldb/include/lldb/API/SBListener.h

@@ -29,6 +29,8 @@ public:
 
   void Clear();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   uint32_t StartListeningForEventClass(SBDebugger &debugger,

lldb/include/lldb/API/SBModule.h

@@ -31,6 +31,8 @@ public:
 
   ~SBModule();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBModuleSpec.h

@@ -24,6 +24,8 @@ public:
 
   const SBModuleSpec &operator=(const SBModuleSpec &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBPlatform.h

@@ -91,6 +91,8 @@ public:
 
   ~SBPlatform();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBProcess.h

@@ -51,6 +51,8 @@ public:
 
   void Clear();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   lldb::SBTarget GetTarget() const;

lldb/include/lldb/API/SBProcessInfo.h

@@ -22,6 +22,8 @@ public:
 
   SBProcessInfo &operator=(const SBProcessInfo &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetName();

lldb/include/lldb/API/SBQueue.h

@@ -28,6 +28,8 @@ public:
 
   ~SBQueue();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBQueueItem.h

@@ -22,6 +22,8 @@ public:
 
   ~SBQueueItem();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBSection.h

@@ -24,6 +24,8 @@ public:
 
   const lldb::SBSection &operator=(const lldb::SBSection &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetName();

lldb/include/lldb/API/SBStream.h

@@ -23,6 +23,8 @@ public:
 
   ~SBStream();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   // If this stream is not redirected to a file, it will maintain a local cache

lldb/include/lldb/API/SBStringList.h

@@ -23,6 +23,8 @@ public:
 
   ~SBStringList();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void AppendString(const char *str);

lldb/include/lldb/API/SBStructuredData.h

@@ -28,6 +28,8 @@ public:
 
   lldb::SBStructuredData &operator=(const lldb::SBStructuredData &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   lldb::SBError SetFromJSON(lldb::SBStream &stream);

lldb/include/lldb/API/SBSymbol.h

@@ -26,6 +26,8 @@ public:
 
   const lldb::SBSymbol &operator=(const lldb::SBSymbol &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetName() const;

lldb/include/lldb/API/SBSymbolContext.h

@@ -29,6 +29,8 @@ public:
 
   ~SBSymbolContext();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const lldb::SBSymbolContext &operator=(const lldb::SBSymbolContext &rhs);

lldb/include/lldb/API/SBSymbolContextList.h

@@ -25,6 +25,8 @@ public:
   const lldb::SBSymbolContextList &
   operator=(const lldb::SBSymbolContextList &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   uint32_t GetSize() const;

lldb/include/lldb/API/SBTarget.h

@@ -55,6 +55,8 @@ public:
 
   const lldb::SBTarget &operator=(const lldb::SBTarget &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   static bool EventIsTargetEvent(const lldb::SBEvent &event);

lldb/include/lldb/API/SBThread.h

@@ -39,6 +39,8 @@ public:
 
   lldb::SBQueue GetQueue() const;
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBThreadCollection.h

@@ -23,6 +23,8 @@ public:
 
   ~SBThreadCollection();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   size_t GetSize();

lldb/include/lldb/API/SBThreadPlan.h

@@ -30,6 +30,8 @@ public:
 
   ~SBThreadPlan();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBTrace.h

@@ -100,6 +100,8 @@ public:
 
   lldb::user_id_t GetTraceUID();
 
+  explicit operator bool() const;
+
   bool IsValid();
 
 protected:

lldb/include/lldb/API/SBTraceOptions.h

@@ -44,6 +44,8 @@ public:
 
   lldb::tid_t getThreadID();
 
+  explicit operator bool() const;
+
   bool IsValid();
 
 protected:

lldb/include/lldb/API/SBType.h

@@ -25,6 +25,8 @@ public:
 
   lldb::SBTypeMember &operator=(const lldb::SBTypeMember &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetName();
@@ -64,6 +66,8 @@ public:
 
   lldb::SBTypeMemberFunction &operator=(const lldb::SBTypeMemberFunction &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetName();
@@ -105,6 +109,8 @@ public:
 
   ~SBType();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   uint64_t GetByteSize();
@@ -235,6 +241,8 @@ public:
 
   lldb::SBTypeList &operator=(const lldb::SBTypeList &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid();
 
   void Append(lldb::SBType type);

lldb/include/lldb/API/SBTypeCategory.h

@@ -22,6 +22,8 @@ public:
 
   ~SBTypeCategory();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   bool GetEnabled();

lldb/include/lldb/API/SBTypeEnumMember.h

@@ -24,6 +24,8 @@ public:
 
   SBTypeEnumMember &operator=(const SBTypeEnumMember &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   int64_t GetValueAsSigned();
@@ -62,6 +64,8 @@ public:
 
   SBTypeEnumMemberList &operator=(const SBTypeEnumMemberList &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid();
 
   void Append(SBTypeEnumMember entry);

lldb/include/lldb/API/SBTypeFilter.h

@@ -24,6 +24,8 @@ public:
 
   ~SBTypeFilter();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   uint32_t GetNumberOfExpressionPaths();

lldb/include/lldb/API/SBTypeFormat.h

@@ -28,6 +28,8 @@ public:
 
   ~SBTypeFormat();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   lldb::Format GetFormat();

lldb/include/lldb/API/SBTypeNameSpecifier.h

@@ -26,6 +26,8 @@ public:
 
   ~SBTypeNameSpecifier();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetName();

lldb/include/lldb/API/SBTypeSummary.h

@@ -23,6 +23,8 @@ public:
 
   ~SBTypeSummaryOptions();
 
+  explicit operator bool() const;
+
   bool IsValid();
 
   lldb::LanguageType GetLanguage();
@@ -79,6 +81,8 @@ public:
 
   ~SBTypeSummary();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   bool IsFunctionCode();

lldb/include/lldb/API/SBTypeSynthetic.h

@@ -32,6 +32,8 @@ public:
 
   ~SBTypeSynthetic();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   bool IsClassCode();

lldb/include/lldb/API/SBUnixSignals.h

@@ -26,6 +26,8 @@ public:
 
   void Clear();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   const char *GetSignalAsCString(int32_t signo) const;

lldb/include/lldb/API/SBValue.h

@@ -28,6 +28,8 @@ public:
 
   ~SBValue();
 
+  explicit operator bool() const;
+
   bool IsValid();
 
   void Clear();

lldb/include/lldb/API/SBValueList.h

@@ -23,6 +23,8 @@ public:
 
   ~SBValueList();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   void Clear();

lldb/include/lldb/API/SBVariablesOptions.h

@@ -26,6 +26,8 @@ public:
 
   ~SBVariablesOptions();
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   bool GetIncludeArguments() const;

lldb/include/lldb/API/SBWatchpoint.h

@@ -25,6 +25,8 @@ public:
 
   const lldb::SBWatchpoint &operator=(const lldb::SBWatchpoint &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
 
   SBError GetError();

lldb/scripts/Python/modify-python-lldb.py

@@ -91,16 +91,6 @@ len_def = "    def __len__(self): return self.%s()"
 eq_def = "    def __eq__(self, other): return isinstance(other, %s) and %s"
 ne_def = "    def __ne__(self, other): return not self.__eq__(other)"
 
-# Called to implement truth value testing and the built-in operation bool();
-# Note that Python 2 uses __nonzero__(), whereas Python 3 uses __bool__()
-# should return False or True, or their integer equivalents 0 or 1.
-# Delegate to self.IsValid() if it is defined for the current lldb object.
-
-if six.PY2:
-    nonzero_def = "    def __nonzero__(self): return self.IsValid()"
-else:
-    nonzero_def = "    def __bool__(self): return self.IsValid()"
-
 # A convenience iterator for SBSymbol!
 symbol_in_section_iter_def = '''
     def symbol_in_section_iter(self, section):
@@ -332,11 +322,6 @@ for line in content.splitlines():
     if one_liner_docstring_pattern.match(line):
         line = char_to_str_xform(line)
 
-    # Look for 'def IsValid(*args):', and once located, add implementation
-    # of truth value testing for this object by delegation.
-    if isvalid_pattern.search(line):
-        new_content.add_line(nonzero_def)
-
     # Pass the original line of content to new_content.
     new_content.add_line(line)
 

lldb/scripts/interface/SBAddress.i

@@ -62,6 +62,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     void
     Clear ();
 

lldb/scripts/interface/SBBlock.i

@@ -30,6 +30,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     %feature("docstring", "
     Get the function name if this block represents an inlined function;
     otherwise, return None.

lldb/scripts/interface/SBBreakpoint.i

@@ -91,6 +91,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     void
     ClearAllBreakpointSites ();
 

lldb/scripts/interface/SBBreakpointLocation.i

@@ -34,6 +34,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     lldb::SBAddress
     GetAddress();
     

lldb/scripts/interface/SBBreakpointName.i

@@ -42,6 +42,8 @@ public:
 
   bool operator!=(const lldb::SBBreakpointName &rhs);
 
+  explicit operator bool() const;
+
   bool IsValid() const;
   
   const char *GetName() const;

lldb/scripts/interface/SBBroadcaster.i

@@ -33,6 +33,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     void
     Clear ();
 

lldb/scripts/interface/SBCommandInterpreter.i

@@ -145,6 +145,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     const char *
     GetIOHandlerControlSequence(char ch);
 

lldb/scripts/interface/SBCommandReturnObject.i

@@ -28,6 +28,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     const char *
     GetOutput ();
 

lldb/scripts/interface/SBCommunication.i

@@ -30,6 +30,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     lldb::SBBroadcaster
     GetBroadcaster ();
 

lldb/scripts/interface/SBCompileUnit.i

@@ -56,6 +56,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     lldb::SBFileSpec
     GetFileSpec () const;
 

lldb/scripts/interface/SBData.i

@@ -31,6 +31,8 @@ public:
     bool
     IsValid();
 
+    explicit operator bool() const;
+
     size_t
     GetByteSize ();
 

lldb/scripts/interface/SBDebugger.i

@@ -152,6 +152,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     void
     Clear ();
 

lldb/scripts/interface/SBDeclaration.i

@@ -24,6 +24,8 @@ namespace lldb {
         bool
         IsValid () const;
 
+        explicit operator bool() const;
+        
         lldb::SBFileSpec
         GetFileSpec () const;
         

lldb/scripts/interface/SBError.i

@@ -101,6 +101,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     bool
     GetDescription (lldb::SBStream &description);
     

lldb/scripts/interface/SBEvent.i

@@ -124,6 +124,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     const char *
     GetDataFlavor ();
 

lldb/scripts/interface/SBFileSpec.i

@@ -45,6 +45,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     bool
     Exists () const;
 

lldb/scripts/interface/SBFrame.i

@@ -59,6 +59,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     uint32_t
     GetFrameID () const;
 

lldb/scripts/interface/SBFunction.i

@@ -55,6 +55,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     const char *
     GetName() const;
     

lldb/scripts/interface/SBInstruction.i

@@ -26,6 +26,8 @@ public:
     bool
     IsValid();
 
+    explicit operator bool() const;
+
     lldb::SBAddress
     GetAddress();
 

lldb/scripts/interface/SBInstructionList.i

@@ -37,6 +37,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     size_t
     GetSize ();
 

lldb/scripts/interface/SBLineEntry.i

@@ -55,6 +55,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     lldb::SBFileSpec
     GetFileSpec () const;
 

lldb/scripts/interface/SBListener.i

@@ -33,6 +33,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     uint32_t
     StartListeningForEventClass (SBDebugger &debugger,
                                  const char *broadcaster_class, 

lldb/scripts/interface/SBModule.i

@@ -130,6 +130,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     void
     Clear();
 

lldb/scripts/interface/SBModuleSpec.i

@@ -21,6 +21,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+    
     void
     Clear();
     

lldb/scripts/interface/SBPlatform.i

@@ -118,6 +118,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     void
     Clear ();
 

lldb/scripts/interface/SBProcess.i

@@ -68,6 +68,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     lldb::SBTarget
     GetTarget() const;
 

lldb/scripts/interface/SBProcessInfo.i

@@ -25,6 +25,8 @@ public:
     bool
     IsValid ();
 
+    explicit operator bool() const;
+
     const char *
     GetName ();
 

lldb/scripts/interface/SBQueue.i

@@ -20,6 +20,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     void
     Clear ();
 

lldb/scripts/interface/SBQueueItem.i

@@ -20,6 +20,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     void
     Clear ();
 

lldb/scripts/interface/SBSection.i

@@ -49,6 +49,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     const char *
     GetName ();
 

lldb/scripts/interface/SBStream.i

@@ -48,6 +48,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     %feature("docstring", "
     //--------------------------------------------------------------------------
     /// If this stream is not redirected to a file, it will maintain a local

lldb/scripts/interface/SBStringList.i

@@ -21,6 +21,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     void
     AppendString (const char *str);
 

lldb/scripts/interface/SBStructuredData.i

@@ -28,6 +28,8 @@ namespace lldb {
         bool
         IsValid() const;
 
+        explicit operator bool() const;
+
         void
         Clear();
 

lldb/scripts/interface/SBSymbol.i

@@ -27,6 +27,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
 
     const char *
     GetName() const;

lldb/scripts/interface/SBSymbolContext.i

@@ -57,6 +57,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     lldb::SBModule        GetModule ();
     lldb::SBCompileUnit   GetCompileUnit ();
     lldb::SBFunction      GetFunction ();

lldb/scripts/interface/SBSymbolContextList.i

@@ -41,6 +41,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+
     uint32_t
     GetSize() const;
 

lldb/scripts/interface/SBTarget.i

@@ -80,6 +80,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     static bool
     EventIsTargetEvent (const lldb::SBEvent &event);
 

lldb/scripts/interface/SBThread.i

@@ -74,6 +74,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     void
     Clear ();
 

lldb/scripts/interface/SBThreadCollection.i

@@ -26,6 +26,8 @@ public:
     bool
     IsValid () const;
 
+    explicit operator bool() const;
+    
     size_t
     GetSize ();
     

lldb/scripts/interface/SBThreadPlan.i

@@ -40,6 +40,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     void
     Clear ();
 
@@ -90,6 +92,8 @@ public:
     bool
     IsValid();
 
+    explicit operator bool() const;
+
     // This section allows an SBThreadPlan to push another of the common types of plans...
     SBThreadPlan
     QueueThreadPlanForStepOverRange (SBAddress &start_address,

lldb/scripts/interface/SBTrace.i

@@ -27,6 +27,8 @@ public:
 
   lldb::user_id_t GetTraceUID();
 
+  explicit operator bool() const;
+
   bool IsValid();
 
 };

lldb/scripts/interface/SBTraceOptions.i

@@ -32,6 +32,8 @@ public:
 
   lldb::tid_t getThreadID();
 
+  explicit operator bool() const;
+
   bool IsValid();
 };
 }

lldb/scripts/interface/SBType.i

@@ -24,6 +24,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+
     const char *
     GetName ();
     
@@ -79,6 +81,8 @@ public:
     bool
     IsValid() const;
 
+    explicit operator bool() const;
+    
     const char *
     GetName ();
     
@@ -196,6 +200,8 @@ public:
     bool
     IsValid();
 
+    explicit operator bool() const;
+
     uint64_t
     GetByteSize();
 
@@ -487,6 +493,8 @@ public:
     bool
     IsValid();
 
+    explicit operator bool() const;
+
     void
     Append (lldb::SBType type);
 

lldb/scripts/interface/SBTypeCategory.i

@@ -25,6 +25,8 @@ namespace lldb {
         bool
         IsValid() const;
 
+        explicit operator bool() const;
+        
         bool
         GetEnabled ();