Packages problems on version 9 under OS X

Using Version 9 on OS X, I've run into some problems with creating packages and accessing them. I've done the following:

• wrote all the function definitions in a notebook and tested that they all worked;


• created a package of the definitions.


• used Install to place the package in the FileNameJoin[{$UserBaseDirectory, "Applications"}] directory;

For good measure I rebooted my computer and restarted Mathematica.

Attempting to load the package gives me nothing, so I simplified everything to see if I'd still have a problem. I made a very simple package:

BeginPackage["testPackage`"]
f::usage = "f[x] returns 2x"
Begin["`Private`"]

f[x_] := 2 x
End[ ]
EndPackage[ ]

I saved and installed it as I described above. Still nothing.

<< testPackage`
Names["testPackage`*"]

{}

I have also tried each of the following:

Get["testPackage`"] (* Doesn't appear to do anything or get any response from Mma *)

Get[FileNameJoin[{$UserBaseDirectory, "Applications", "testPackage`"}]]
$Failed

Needs["testPackage`"]
Needs::nocont: Context testPackage` was not created when Needs was evaluated. >>

Nothing works.

You can see the package installed in the ...Mathematica/Applications directory:

I followed (or at least thought I followed) the recommendations in How to install packages?

I thought doing so would place the package in a path known to the front end.

What have I missed?

Answer

If you're creating a package using a notebook (with AutoGeneratedPackage -> Automatic) you need to write all your code in "Initialization Cells". Everything else is commented out.