Pkg Config

Stratego -- Strategies for Program Transformation

Pkg-config

In this release we have introduced pkg-config for locating packages and their configuration. The use of pkg-config has several advantages:

Distributions of packages that have been created using a certain Stratego/XT are more likely to work on future versions of Stratego/XT. Thus, package don't have to be re-distributed if a new Stratego/XT comes out.

Users of packages that use Stratego/XT don't need to configure this package with the location of Stratego/XT. Pkg-config is used to find the location of Stratego/XT on the system of the user.

Internally, the installation of Stratego/XT is less complicated. The installation of packages in the directory local-baseline is no longer necessary.

Users can use pkg-config to pass the right includes paths to the Stratego compiler.

For Stratego/XT Users

Installation

Stratego/XT users need to have pkg-config installed on their system before they install Stratego/XT. Pkg-config 0.15 is widely deployed, since it used by most GNOME packages, and should do the job. We don't know what the exact minimal required version is.

You still need to configure Stratego/XT with the location the ATerm library and the SDF2 Bundle (--with-aterm) and (--with-sdf). This will be no longer necessary when future versions of the SDF2 Bundle and the ATerm library support pkg-config. Internally, the PKG_CONFIG_PATH is set and pkg-config is used to find the required packages.

Compiling your Program

For compiling your own Stratego programs, you can now optionally use pkg-config to find the flags that you need to pass to strc.

$ pkg-config --variable=strcflags java-front
-I /pkg/java-front/2005-03-30-14-06/share/sdf/java-front \
  -I /pkg/java-front/2005-03-30-14-06/share/java-front

In my .bashrc I've defined an alias strcflags to make this common command more compact:

alias strcflags="pkg-config --variable=strcflags "

You can also specify multiple packages:

$ strcflags java-front dryad
-I /pkg/java-front/2005-03-30-14-06/share/sdf/java-front \
-I /pkg/java-front/2005-03-30-14-06/share/java-front \
-I /pkg/dryad/2005-04-04-15-24/share/dryad \
-I /pkg/dryad/2005-04-04-15-24/share/sdf/dryad

Obviously, this is much easier then mentioning all the specific paths of these packages.

For Users of Packages that use Stratego/XT

If the developer of this package releases a new version, then this package is more likely to work on future versions of Stratego/XT. You don't need to configure the package with locations of aterm, sdf, and strategoxt, since pkg-config is used to find them. Hence, the package is easier to install.

If you install Stratego/XT in a non standard location, then you need to set the PKG_CONFIG_PATH. See SomeTopic^?.

For Developers of Packages that use Stratego/XT

You need pkg-config, preferebly 0.17.2, which is available in the Nix Packages Collection. The Autoconf macro XT_USE_XT_PACKAGES no longer defines configure arguments, but uses pkg-config to find the location of packages. The old style of explicit configuration is still available in the macro XT_EXPLICTLY_USE_XT_PACKAGES. Please note that your package is more likely to break on future Stratego/XT versions if you use this macro.

For Stratego/XT Developers

You need pkg-config, preferebly 0.17.2, which is available in the Nix Packages Collection. A Subversion checkout of Stratego/XT requires configuration --with-strategoxt for the baseline Stratego/XT, i.e. pkg-config is not used to find the baseline Stratego/XT, since this very fragile. Internally, the PKG_CONFIG_PATH is set to the configuration flags that you provide.