Implement in module

Given test.in containing something along these lines:

foo = $foo$

Now we can do:

using in

file{test}: in{test.in}
file{test}: foo = FOO

The alternative variable substitution symbol can be specified with the
in.symbol variable and lax (instead of the default strict) mode with
in.substitution. For example:

file{test}: in.symbol = '@'
file{test}: in.substitution = lax

1 files changed, 0 insertions, 27 deletions

diff --git a/build2/target.hxx b/build2/target.hxx
index 515a082..aad5331 100644
--- a/build2/target.hxx
+++ b/build2/target.hxx
@@ -1607,33 +1607,6 @@ namespace build2
     virtual const target_type& dynamic_type () const {return static_type;}
   };
 
-  // This is the venerable .in ("input") file that needs some kind of
-  // preprocessing.
-  //
-  // One interesting aspect of this target type is that the prerequisite
-  // search is target-dependent. Consider:
-  //
-  // hxx{version}: in{version.hxx} // version.hxx.in -> version.hxx
-  //
-  // Having to specify the header extension explicitly is inelegant. Instead
-  // what we really want to write is this:
-  //
-  // hxx{version}: in{version}
-  //
-  // But how do we know that in{version} means version.hxx.in? That's where
-  // the target-dependent search comes in: we take into account the target
-  // we are a prerequisite of.
-  //
-  class in: public file
-  {
-  public:
-    using file::file;
-
-  public:
-    static const target_type static_type;
-    virtual const target_type& dynamic_type () const {return static_type;}
-  };
-
   // Common documentation file targets.
   //
   class doc: public file