netcdf - enable fortran support

Formula/netcdf.rb

@@ -6,43 +6,33 @@ class Netcdf <Formula
   md5 '79c5ff14c80d5e18dd8f1fceeae1c8e1'
 
   depends_on 'hdf5'
+  depends_on 'gfortran' if ARGV.include? '--fortran'
+
+  def options
+    [['--fortran', 'Compile with Fortran support']]
+  end
 
   def install
-    # HDF5 is required to create and access files
-    # in the NetCDF version 4 format.
+    # HDF5 is required to create and access files in the version 4 format
     hdf5 = Formula.factory('hdf5')
 
-    system "./configure", "--prefix=#{prefix}",
-                          "--disable-dependency-tracking",
-                          "--with-hdf5=#{hdf5.prefix}",
-                          "--enable-netcdf4",
-                          "--disable-fortran",  # Until issue 72 is resolved.
-                          "--enable-shared"
+    args = ["--disable-dependency-tracking",
+            "--prefix=#{prefix}",
+            "--with-hdf5=#{hdf5.prefix}",
+            "--enable-netcdf4",
+            "--enable-shared"]
+    args << "--disable-fortran" unless ARGV.include? '--fortran'
+
+    system "./configure", *args
     system "make install"
   end
 
-  def caveats
-    caveats = <<-EOS
-This brew of NetCDF does not include Fortran support.
-Fortran support will be added once the following issue
-is resolved:
+  def caveats; <<-EOS
+To build with (experimental) fortran support:
+  brew install netcdf --fortran
 
-  http://github.com/mxcl/homebrew/issues/72
-
-If you have a Fortran compiler and would like to enable
-NetCDF support for Fortran compilers, execute:
-
-  brew edit netcdf
-
-Comment out the configure argument disabling Fortran
-and re-install.  You may have to set FCFLAGS and FFLAGS
-to be consistant with Homebrew's use of C compilers in
-order for the brew to install correctly.
-
-Be aware that the Homebrew project may not be able to
-provide support for any issues that arise during
-compilation when Fortran is enabled until a Fortran
-compiler is officially supported.
+You may have to set FCFLAGS and FFLAGS to be consistant with Homebrew's use
+of C compilers in order for the brew to install correctly.
     EOS
   end
 end