ENH: Updated exporting and importing of targets to support libraries and configurations.

  - Created cmExportFileGenerator hierarchy to implement export file generation
  - Installed exports use per-config import files loaded by a central one.
  - Include soname of shared libraries in import information
  - Renamed PREFIX to NAMESPACE in INSTALL(EXPORT) and EXPORT() commands
  - Move addition of CMAKE_INSTALL_PREFIX to destinations to install generators
  - Import files compute the installation prefix relative to their location when loaded
  - Add mapping of importer configurations to importee configurations
  - Rename IMPORT targets to IMPORTED targets to distinguish from windows import libraries
  - Scope IMPORTED targets within directories to isolate them
  - Place all properties created by import files in the IMPORTED namespace
  - Document INSTALL(EXPORT) and EXPORT() commands.
  - Document IMPORTED signature of add_executable and add_library
  - Enable finding of imported targets in cmComputeLinkDepends

1 files changed, 19 insertions, 12 deletions

diff --git a/Source/cmExportCommand.h b/Source/cmExportCommand.h
index c79f46d..f424501 100644
--- a/Source/cmExportCommand.h
+++ b/Source/cmExportCommand.h
@@ -55,7 +55,7 @@ public:
   virtual const char* GetTerseDocumentation()
     {
     return
-      "Write out the dependency information for all targets of a project.";
+      "Export targets from the build tree for use by outside projects.";
     }
 
   /**
@@ -64,15 +64,23 @@ public:
   virtual const char* GetFullDocumentation()
     {
     return
-      "  export(TARGETS tgt1 ... tgtN [PREFIX <prefix>] FILE <filename> "
-      "[APPEND])\n"
-      "Create a file that can be included into a CMake listfile with the "
-      "INCLUDE command.  The file will contain a number of SET commands "
-      "that will set all the variables needed for library dependency "
-      "information.  This should be the last command in the top level "
-      "CMakeLists.txt file of the project.  If the APPEND option is "
-      "specified, the SET commands will be appended to the given file "
-      "instead of replacing it.";
+      "  export(TARGETS [target1 [target2 [...]]] [NAMESPACE <namespace>]\n"
+      "         FILE <filename>)\n"
+      "Create a file <filename> that may be included by outside projects to "
+      "import targets from the current project's build tree.  "
+      "This is useful during cross-compiling to build utility executables "
+      "that can run on the host platform in one project and then import "
+      "them into another project being compiled for the target platform.  "
+      "If the NAMESPACE option is given the <namespace> string will be "
+      "prepended to all target names written to the file.  "
+      "If a library target is included in the export but "
+      "a target to which it links is not included the behavior is "
+      "unspecified."
+      "\n"
+      "The file created by this command is specific to the build tree and "
+      "should never be installed.  "
+      "See the install(EXPORT) command to export targets from an "
+      "installation tree.";
     }
 
   cmTypeMacro(cmExportCommand, cmCommand);
@@ -80,8 +88,7 @@ public:
 private:
   cmCommandArgumentGroup ArgumentGroup;
   cmCAStringVector Targets;
-  cmCAEnabler Append;
-  cmCAString Prefix;
+  cmCAString Namespace;
   cmCAString Filename;
 };