Tutorial: Refactor MathFunctions code

Propagate the refactor in Step 10 MathFunctions through all of the
steps. Use MathFunctions/MathFunctions.cxx instead of Tutorial.cxx
to determine which sqrt library is called. Adds .h files which
correspond to their .cxx files by name.

7 files changed, 54 insertions, 45 deletions

diff --git a/Help/guide/tutorial/Step10/CMakeLists.txt b/Help/guide/tutorial/Step10/CMakeLists.txt
index 5c661aa..2dd6db5 100644
--- a/Help/guide/tutorial/Step10/CMakeLists.txt
+++ b/Help/guide/tutorial/Step10/CMakeLists.txt
@@ -16,22 +16,15 @@ target_compile_options(tutorial_compiler_flags INTERFACE
   "$<${msvc_cxx}:$<BUILD_INTERFACE:-W3>>"
 )
 
-# should we use our own math functions
-option(USE_MYMATH "Use tutorial provided math implementation" ON)
-
-# configure a header file to pass some of the CMake settings
-# to the source code
+# configure a header file to pass the version number only
 configure_file(TutorialConfig.h.in TutorialConfig.h)
 
 # add the MathFunctions library
-if(USE_MYMATH)
-  add_subdirectory(MathFunctions)
-  list(APPEND EXTRA_LIBS MathFunctions)
-endif()
+add_subdirectory(MathFunctions)
 
 # add the executable
 add_executable(Tutorial tutorial.cxx)
-target_link_libraries(Tutorial PUBLIC ${EXTRA_LIBS} tutorial_compiler_flags)
+target_link_libraries(Tutorial PUBLIC MathFunctions tutorial_compiler_flags)
 
 # add the binary tree to the search path for include files
 # so that we will find TutorialConfig.h
diff --git a/Help/guide/tutorial/Step10/MathFunctions/CMakeLists.txt b/Help/guide/tutorial/Step10/MathFunctions/CMakeLists.txt
index fa73321..6f6c430 100644
--- a/Help/guide/tutorial/Step10/MathFunctions/CMakeLists.txt
+++ b/Help/guide/tutorial/Step10/MathFunctions/CMakeLists.txt
@@ -1,32 +1,51 @@
-# first we add the executable that generates the table
-add_executable(MakeTable MakeTable.cxx)
-
-# add the command to generate the source code
-add_custom_command(
-  OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/Table.h
-  COMMAND MakeTable ${CMAKE_CURRENT_BINARY_DIR}/Table.h
-  DEPENDS MakeTable
-  )
-
-# add the main library
-add_library(MathFunctions
-            mysqrt.cxx
-            ${CMAKE_CURRENT_BINARY_DIR}/Table.h
-            )
+# add the library that runs
+add_library(MathFunctions MathFunctions.cxx)
 
 # state that anybody linking to us needs to include the current source dir
 # to find MathFunctions.h, while we don't.
-# state that we depend on our binary dir to find Table.h
 target_include_directories(MathFunctions
-          INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}
-          PRIVATE   ${CMAKE_CURRENT_BINARY_DIR}
-          )
+                           INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}
+                           )
 
-# link our compiler flags interface library
-target_link_libraries(MathFunctions tutorial_compiler_flags)
+# should we use our own math functions
+option(USE_MYMATH "Use tutorial provided math implementation" ON)
+if(USE_MYMATH)
+
+  target_compile_definitions(MathFunctions PRIVATE "USE_MYMATH")
+
+  # first we add the executable that generates the table
+  add_executable(MakeTable MakeTable.cxx)
+  target_link_libraries(MakeTable PRIVATE tutorial_compiler_flags)
+
+  # add the command to generate the source code
+  add_custom_command(
+    OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/Table.h
+    COMMAND MakeTable ${CMAKE_CURRENT_BINARY_DIR}/Table.h
+    DEPENDS MakeTable
+    )
+
+  # library that just does sqrt
+  add_library(SqrtLibrary STATIC
+              mysqrt.cxx
+              ${CMAKE_CURRENT_BINARY_DIR}/Table.h
+              )
+
+  # state that we depend on our binary dir to find Table.h
+  target_include_directories(SqrtLibrary PRIVATE
+                             ${CMAKE_CURRENT_BINARY_DIR}
+                             )
+
+  target_link_libraries(SqrtLibrary PUBLIC tutorial_compiler_flags)
+  target_link_libraries(MathFunctions PRIVATE SqrtLibrary)
+endif()
+
+target_link_libraries(MathFunctions PUBLIC tutorial_compiler_flags)
 
 # install libs
 set(installable_libs MathFunctions tutorial_compiler_flags)
+if(TARGET SqrtLibrary)
+  list(APPEND installable_libs SqrtLibrary)
+endif()
 install(TARGETS ${installable_libs} DESTINATION lib)
 # install include headers
 install(FILES MathFunctions.h DESTINATION include)
diff --git a/Help/guide/tutorial/Step10/MathFunctions/MathFunctions.cxx b/Help/guide/tutorial/Step10/MathFunctions/MathFunctions.cxx
index 0145300..c0991b9 100644
--- a/Help/guide/tutorial/Step10/MathFunctions/MathFunctions.cxx
+++ b/Help/guide/tutorial/Step10/MathFunctions/MathFunctions.cxx
@@ -10,6 +10,7 @@
 namespace mathfunctions {
 double sqrt(double x)
 {
+// which square root function should we use?
 #ifdef USE_MYMATH
   return detail::mysqrt(x);
 #else
diff --git a/Help/guide/tutorial/Step10/MathFunctions/MathFunctions.h b/Help/guide/tutorial/Step10/MathFunctions/MathFunctions.h
index cd36bcc..1e916e1 100644
--- a/Help/guide/tutorial/Step10/MathFunctions/MathFunctions.h
+++ b/Help/guide/tutorial/Step10/MathFunctions/MathFunctions.h
@@ -1 +1,3 @@
-double mysqrt(double x);
+namespace mathfunctions {
+double sqrt(double x);
+}
diff --git a/Help/guide/tutorial/Step10/MathFunctions/mysqrt.cxx b/Help/guide/tutorial/Step10/MathFunctions/mysqrt.cxx
index 7d80ee9..8153f18 100644
--- a/Help/guide/tutorial/Step10/MathFunctions/mysqrt.cxx
+++ b/Help/guide/tutorial/Step10/MathFunctions/mysqrt.cxx
@@ -5,6 +5,8 @@
 // include the generated table
 #include "Table.h"
 
+namespace mathfunctions {
+namespace detail {
 // a hack square root calculation using simple operations
 double mysqrt(double x)
 {
@@ -31,3 +33,5 @@ double mysqrt(double x)
 
   return result;
 }
+}
+}
diff --git a/Help/guide/tutorial/Step10/TutorialConfig.h.in b/Help/guide/tutorial/Step10/TutorialConfig.h.in
index e23f521..7e4d7fa 100644
--- a/Help/guide/tutorial/Step10/TutorialConfig.h.in
+++ b/Help/guide/tutorial/Step10/TutorialConfig.h.in
@@ -1,4 +1,3 @@
 // the configured options and settings for Tutorial
 #define Tutorial_VERSION_MAJOR @Tutorial_VERSION_MAJOR@
 #define Tutorial_VERSION_MINOR @Tutorial_VERSION_MINOR@
-#cmakedefine USE_MYMATH
diff --git a/Help/guide/tutorial/Step10/tutorial.cxx b/Help/guide/tutorial/Step10/tutorial.cxx
index b3c6a4f..37a0333 100644
--- a/Help/guide/tutorial/Step10/tutorial.cxx
+++ b/Help/guide/tutorial/Step10/tutorial.cxx
@@ -1,15 +1,11 @@
 // A simple program that computes the square root of a number
-#include <cmath>
 #include <iostream>
+#include <sstream>
 #include <string>
 
+#include "MathFunctions.h"
 #include "TutorialConfig.h"
 
-// should we include the MathFunctions header?
-#ifdef USE_MYMATH
-#  include "MathFunctions.h"
-#endif
-
 int main(int argc, char* argv[])
 {
   if (argc < 2) {
@@ -23,12 +19,7 @@ int main(int argc, char* argv[])
   // convert input to double
   const double inputValue = std::stod(argv[1]);
 
-  // which square root function should we use?
-#ifdef USE_MYMATH
-  const double outputValue = mysqrt(inputValue);
-#else
-  const double outputValue = sqrt(inputValue);
-#endif
+  const double outputValue = mathfunctions::sqrt(inputValue);
 
   std::cout << "The square root of " << inputValue << " is " << outputValue
             << std::endl;