anchor.diff:  
     l_set_work = buildEnv {
       name = "l-set-work";
  +    ignoreCollisions = true;
       paths = [
         l_set_base
         l_set_dev
  
positive.code: 
    l_set_misc = buildEnv {
      name = "l-set-misc";
      paths = [
        pidgin
        texLiveFull
  
negative.code: 
    l_set_av = buildEnv {
      name = "l-set-av";
      ignoreCollisions = true;
      paths = [
        scrot
        geeqie
  