[Lemon-devel] Lemon Project Template enhancement

[Alpár Jüttner]

Hi,

Let me draw your attention to a recent update in the project template
repository at http://lemon.cs.elte.hu/hg/lemon-project-template

(This template is a preconfigured CMAKE build environment with the
purpose of easing the pain of starting a development project that uses
LEMON. See http://lemon.cs.elte.hu/trac/lemon/wiki/ProjectTemplate for
more info.)

As you may already know, the project template allows you to use LEMON
without installing it, simply by copying the full LEMON source into the
'lemon' subdirectory. The current version provides two enhancements to
this.
      * In addition to 'lemon' is also checks 'deps/lemon' for the LEMON
        source tree and
      * (more importantly) you can overwrite this location by the
        LEMON_SOURCE_ROOT_DIR CMAKE variable.

This latter option has two important use-cases.

Firstly, its enough to keep a single checkout of LEMON, then you can use
it in all of your projects

        cd myproject
        mkdir build
        cd build
        cmake -DLEMON_SOURCE_ROOT_DIR=/lemon/source/code/dir ..
        make

Secondly, you can easily test and use your code with different LEMON
versions in parallel:
        
        cd myproject
        hg clone http://lemon.cs.elte.hu/hg/lemon-main lemon-main
        hg clone http://lemon.cs.elte.hu/hg/lemon -r r1.2.1 lemon-1.2.1
        
        mkdir build; cd build
        cmake -DLEMON_SOURCE_ROOT_DIR=../lemon-main ..
        make
        cd ..
        
        mkdir build-1.2.1; cd build-1.2.1
        cmake -DLEMON_SOURCE_ROOT_DIR=../lemon-1.2.1 ..
        make

Regards,
Alpár