Bug fixes for handling attr names like "@foo"

Bug fixes for handling attr names like "@foo"

Squashed commit of the following:

commit 7607ae11345e64bbb5e1b2aa6ac50b2a4fde2154
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 11:18:38 2010 -0600

    Add changes for bug fix

commit bc41986f83d549a00b9b1eb2b50590a41546d3dc
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 11:07:09 2010 -0600

    Quotemeta one last name

commit 4a5cc686e344c2dedbf15d9c91536edb1f0e40b5
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 11:06:00 2010 -0600

    start fixing use of non-alpha names and remove more unused vars

commit 8beb437913f2f1c194e78597da4af48cf22dba23
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 11:04:43 2010 -0600

    More type fixes for values

commit ff707cbf2bdb2adfc2c9100fc0cc6e4a24b6c1b6
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 11:03:57 2010 -0600

    Fix value for has spaces

commit b2dc594248b2f7c88afce07c9561b5059806ccd0
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 11:03:30 2010 -0600

    Add reader for !req

commit 85fe6c1e51c2e53483312a41090430df3c26916c
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 10:59:52 2010 -0600

    Improve non-alpha attr tests. Need to include constraints and required attrs to smoke out bugs.

    Also use with_immutable for tests

commit 3c3def7dc1347edf8b0316467c3c2439fa7fc6f6
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 10:58:04 2010 -0600

    Remove unused variables from the environment for accessors when evaling code

commit 4510a53ce87a440ed9bb9a2a028053e6c93ad0f3
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 10:56:21 2010 -0600

    Remove more unused variables

commit 6c40837349c828f159ea8dd752d847991e43ddf1
Author: Dave Rolsky <autarch@urth.org>
Date:   Sun Jan 17 10:51:30 2010 -0600

    Remove unused variable