Expressions

- Fixed some compiler warnings.
- Added DOM detection of primitives: int, double, string.
- Began implementation of DOM task access.
- Implemented support for .startswith, .endswith, .word and .noword.
- Removed obsolete subst.t.cpp.

src/DOM.h

@@ -41,6 +41,7 @@ public:
   void set (const std::string&, const std::string&);
 
 private:
+  bool is_primitive (const std::string&);
 };
 
 #endif