Bug2184: should not grey Effect menu when selection is point

src/Menus.cpp

@@ -583,11 +583,11 @@ void MenuManager::UpdateMenus( bool checkActive )
    //to actually do the 'select all' to make the command valid.
 
    for ( const auto &enabler : Enablers() ) {
+      auto actual = enabler.actualFlags();
       if (
-         enabler.applicable( project ) &&
-         (flags & enabler.actualFlags) == enabler.actualFlags
+         enabler.applicable( project ) && (flags & actual) == actual
       )
-         flags2 |= enabler.possibleFlags;
+         flags2 |= enabler.possibleFlags();
    }
 
    auto &commandManager = CommandManager::Get( project );
@@ -654,13 +654,14 @@ bool MenuManager::TryToMakeActionAllowed(
    auto iter = enablers.begin(), end = enablers.end();
    while ((flags & flagsRqd) != flagsRqd && iter != end) {
       const auto &enabler = *iter;
+      auto actual = enabler.actualFlags();
       auto MissingFlags = (~flags & flagsRqd);
       if (
          // Do we have the right precondition?
-         (flags & enabler.actualFlags) == enabler.actualFlags
+         (flags & actual) == actual
       &&
          // Can we get the condition we need?
-         (MissingFlags & enabler.possibleFlags) == MissingFlags
+         (MissingFlags & enabler.possibleFlags()) == MissingFlags
       ) {
          // Then try the function
          enabler.tryEnable( project, flagsRqd );

src/ProjectAudioManager.cpp

@@ -1089,8 +1089,8 @@ void ProjectAudioManager::DoPlayStopSelect()
 #include "CommonCommandFlags.h"
 
 static RegisteredMenuItemEnabler stopIfPaused{{
-   PausedFlag,
-   AudioIONotBusyFlag,
+   []{ return PausedFlag; },
+   []{ return AudioIONotBusyFlag; },
    []( const AudacityProject &project ){
       return MenuManager::Get( project ).mStopIfWasPaused; },
    []( AudacityProject &project, CommandFlag ){

src/commands/CommandFlag.h

@@ -101,12 +101,17 @@ public:
 // then the enabler will be invoked (unless the menu item is constructed with
 // the useStrictFlags option, or the applicability test first returns false).
 // The item's full set of required flags is passed to the function.
+
+// Computation of the flags is delayed inside a function -- because often you
+// need to name a statically allocated CommandFlag, or a bitwise OR of some,
+// while they may not have been initialized yet, during static initialization.
 struct MenuItemEnabler {
+   using Flags = std::function< CommandFlag() >;
    using Test = std::function< bool( const AudacityProject& ) >;
    using Action = std::function< void( AudacityProject&, CommandFlag ) >;
 
-   const CommandFlag &actualFlags;
-   const CommandFlag &possibleFlags;
+   const Flags actualFlags;
+   const Flags possibleFlags;
    Test applicable;
    Action tryEnable;
 };

src/menus/EditMenus.cpp

@@ -1172,23 +1172,23 @@ auto selectAll = []( AudacityProject &project, CommandFlag flagsRqd ){
 };
 
 RegisteredMenuItemEnabler selectTracks{{
-   TracksExistFlag,
-   TracksSelectedFlag,
+   []{ return TracksExistFlag; },
+   []{ return TracksSelectedFlag; },
    canSelectAll,
    selectAll
 }};
 
 RegisteredMenuItemEnabler selectWaveTracks{{
-   WaveTracksExistFlag,
-   TimeSelectedFlag | WaveTracksSelectedFlag | CutCopyAvailableFlag,
+   []{ return WaveTracksExistFlag; },
+   []{ return TimeSelectedFlag | WaveTracksSelectedFlag | CutCopyAvailableFlag; },
    canSelectAll,
    selectAll
 }};
 
 // Also enable select for the noise reduction case.
 RegisteredMenuItemEnabler selectWaveTracks2{{
-   WaveTracksExistFlag,
-   NoiseReductionTimeSelectedFlag | WaveTracksSelectedFlag | CutCopyAvailableFlag,
+   []{ return WaveTracksExistFlag; },
+   []{ return NoiseReductionTimeSelectedFlag | WaveTracksSelectedFlag | CutCopyAvailableFlag; },
    canSelectAll,
    selectAll
 }};