frobtads.rb

require 'formula'

class Tads2Compiler <Formula
  url 'http://www.tads.org/frobtads/frobtads-t2compiler-0.13.tar.gz'
  md5 '12caf94d9c1e646ae04b44da0df83a30'
end

class Tads3Compiler <Formula
  url 'http://www.tads.org/frobtads/frobtads-t3compiler-0.13.tar.gz'
  md5 '231d359f389be3d28e8134a2b832dd70'
end

class Frobtads <Formula
  url 'http://www.tads.org/frobtads/frobtads-0.13.tar.gz'
  homepage 'http://www.tads.org/frobtads.htm'
  md5 'b6f25787b9ff7b89931d765046c68642'

  def options
    [
      ['--tads2-compiler', "Include TADS 2 compiler"],
      ['--tads3-compiler', "Include TADS 3 compiler"]
    ]
  end

  def install
    workdir=Pathname.getwd

    if ARGV.include? '--tads2-compiler'
      Tads2Compiler.new.brew { workdir.install Dir["*"] }
    end

    if ARGV.include? '--tads3-compiler'
      Tads3Compiler.new.brew { workdir.install Dir["*"] }
    end

    system "./configure", "--disable-dependency-tracking",
                          "--prefix=#{prefix}"
    system "make install"
  end
end

Attempting to achieve this:

There are no extra configuration steps required to build the compilers. Just unpack them inside the FrobTADS directory and reconfigure the package. The FrobTADS configuration script will detect the presence of the compiler sources and build them along with the interpreter. For example, if you previously unpacked FrobTADS in

~/downloads/frobtads-0.11

and your downloaded TADS 3 compiler package is

~/downloads/frobtads-t3compiler-0.11.tar.gz

you can unpack the compiler with:

cd ~/downloads/frobtads-0.11
tar -xzf ~/downloads/frobtads-t3compiler-0.11.tar.gz

But it fails because both the main frobtads archive and the compiler archives both contain directories named "t3compiler" and the workdir.install call fails, even though the two similarly-named directories have different contents.