Add a header file to hold strings between string and feature freeze

src/CMakeLists.txt

@@ -328,6 +328,7 @@ list( APPEND SOURCES
       UIHandle.h
       UndoManager.cpp
       UndoManager.h
+      UnusedStrings.h
       UserException.cpp
       UserException.h
       ViewInfo.cpp

src/UnusedStrings.h

@@ -0,0 +1,80 @@
+/**********************************************************************
+ 
+ Audacity: A Digital Audio Editor
+ 
+ @file UnusedStrings.h
+ 
+ Paul Licameli
+ 
+ **********************************************************************/
+
+/*
+This file contains strings and comments put into the source code tree for the
+string freeze of a release, but while not yet in feature freeze.  This allows
+the translation catalog template, locale/audacity.pot, to stabilize long enough
+in advance of the release, that translators have enough opportunity to update
+the language-specific catalogs.
+
+These strings, and their i18n-hint comments, can be cut and pasted elsewhere
+during the continued development in string freeze.
+
+Some example strings are also given first, to document the syntax.
+ */
+
+// //////////////////////////////////////////////// Begin examples
+
+// A translated string may also have an accompanying special comment
+
+// i18n-hint to lower oneself
+XO("Get down"),
+
+/* i18n-hint An example of a longer special comment that can wrap lines.
+ These comments must begin with the special word i18n-hint and immediately
+ precede the source code line with the opening quotation mark.  The translators
+ will see this comment text in the generated .po files, which they edit and
+ complete.  This comment can give hints about unusual words, or the grammatical
+ form of an English word (such as whether it's meant as noun or verb) when that
+ is not clear from context.
+ */
+XO("Get down"),
+
+XO(
+   /* i18n-hint one more example of alternative correct placement of an
+    internationalization comment.  All comments on different occurrences of the
+    same string are collected in the template file.  */
+   "Get down"),
+
+// Next is an example of a string with a disambiguating context.  This allows
+// one English string to have more than one entry in the translation catalog.
+// The context string is not itself seen by users or translated by translators.
+// It only allows the code at runtime to choose the correct translation.
+
+// i18n-hint Have fun and dance
+XC("Get down", "party"),
+
+// i18n-hint Obtain the underfeathers of a goose
+XC("Get down", "pillows"),
+
+// Strings may have blanks in which names are substituted, such as a file name.
+// For good internationalization, allowing for variations of grammar between
+// languages, and giving translators the needed context, we substitute names
+// into larger phrases.  Do not build up messages by concatenating less complete
+// phrases.
+XO("Your batch command of %s was not recognized."),
+
+// Sometimes strings must be given as singular-plural pairs.  The translation
+// system may make more or fewer than two entries in the catalog, depending
+// on the grammatical rules of the language.  The 0 is a placeholder for an
+// expression in real code that is used to choose the proper string at
+// lookup time.
+// Also %d is a blank appropriate for a number instead of a name.
+
+// i18n-hint
+XP("Got down one time", "Got down %d times", 0),
+
+// Finally, singular-plural pairs may also have context strings.
+
+// i18n-hint Obtained underfeathers of geese on one or more occasions
+XPC("Got down one time", "Got down %d times", 0, "pillows"),
+
+// //////////////////////////////////////////////// End examples

src/prefs/GUIPrefs.cpp

@@ -329,9 +329,14 @@ wxString GUIPrefs::SetLang( const wxString & lang )
       Internat::SetCeeNumberFormat();
 #endif
 
-   // Unused strings that we want to be translated, even though
-   // we're not using them yet...
-   using future1 = decltype( XO("Master Gain Control") );
+   using future1 = decltype(
+      // The file of unused strings is part of the source tree scanned by
+      // xgettext when compiling the catalog template audacity.pot.
+      // Including it here doesn't change that but does make the C++ compiler
+      // check for correct syntax, but also generate no object code for them.
+#include "UnusedStrings.h"
+      0
+   );
 
 #ifdef __WXMAC__
       wxApp::s_macHelpMenuTitleName = _("&Help");