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, 37 insertions, 0 deletions

diff --git a/build2/in/init.hxx b/build2/in/init.hxx
new file mode 100644
index 0000000..82879fb
--- /dev/null
+++ b/build2/in/init.hxx
@@ -0,0 +1,37 @@
+// file      : build2/in/init.hxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2018 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_IN_INIT_HXX
+#define BUILD2_IN_INIT_HXX
+
+#include <build2/types.hxx>
+#include <build2/utility.hxx>
+
+#include <build2/module.hxx>
+
+namespace build2
+{
+  namespace in
+  {
+    bool
+    base_init (scope&,
+               scope&,
+               const location&,
+               unique_ptr<module_base>&,
+               bool,
+               bool,
+               const variable_map&);
+
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
+  }
+}
+
+#endif // BUILD2_IN_INIT_HXX