Prompt

- Prompt composition is factored out into a separate function. The prompt is
  going to be a big feature, and needs room for processing.

src/CMakeLists.txt

@@ -5,6 +5,7 @@ include_directories (${CMAKE_SOURCE_DIR}
 
 set (tasksh_SRCS diag.cpp
                  help.cpp
+                 prompt.cpp
                  Color.cpp Color.h
                  text.cpp  text.h)
 

src/main.cpp

@@ -35,14 +35,18 @@
 #include <readline/history.h>
 #endif
 
+// tasksh commands.
 int cmdHelp ();
 int cmdDiagnostics ();
+std::string composePrompt ();
 
 ////////////////////////////////////////////////////////////////////////////////
 static int commandLoop ()
 {
-  // TODO Compose prompt.
-  std::string prompt = "task> ";
+  // TODO Local data: timer, context stack.  No globals.
+
+  // Compose the prompt.
+  std::string prompt = composePrompt ();
 
   // Display prompt, get input.
   char *line_read = readline (prompt.c_str ());

src/prompt.cpp

@@ -0,0 +1,36 @@
+////////////////////////////////////////////////////////////////////////////////
+//
+// Copyright 2006 - 2014, Paul Beckingham, Federico Hernandez.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+// http://www.opensource.org/licenses/mit-license.php
+//
+////////////////////////////////////////////////////////////////////////////////
+
+#include <cmake.h>
+#include <string>
+
+////////////////////////////////////////////////////////////////////////////////
+std::string composePrompt ()
+{
+  return "task> ";
+}
+
+////////////////////////////////////////////////////////////////////////////////