freeze(), unfreeze(), and nested key support

[Yves33]

The following patch addresses issues 110 (and closely related 117) and 121
This is my first pull request! be indulgent!

#110 Deep setattr and gettattr when attribute names contain '.'
the patch enables
d=Dict()
var keypath='path.to.nested.key'
d[ keypath ]='test'
print(d [ keypass] )

#121 Is it possible to forbid accessing missing keys?
adict returns an empty dict when trying to access non existing keys
d=Dict()
assert d.a.b.c == {}
the patch introduces d.freeze() and d.unfreeze().
When the dict is frozen, you cannot create new keys (keyError raised) but you can modify existing ones
The patch overrides default get method to

• get frozen/unfrozen state
• freeze dict
• return d[key] if key exists otherwise default
  -restore frozen/unfrozen state

[coveralls]

Coverage remained the same at 100.0% when pulling 1822161 on Yves33:master into 66d8811 on mewwts:master.

[evanjtravis]

Big fan of this PR.

[mewwts]

Hey! Can you split this PR into two where one has the freeze-functionality and another one for nested keys? In the new PR for nested keys, can you also outline the differences to this PR #119?
Thank you 🙏

[Yves33]

I can try, but although I'm fairly confortable with python, I'm TOTALLY new to git and pullrequests... How can I do that? De: "Mats Julian Olsen" <notifications@github.com> À: "mewwts/addict" <addict@noreply.github.com> Cc: "Yves Le Feuvre" <yves.le-feuvre@u-bordeaux.fr>, "Author" <author@noreply.github.com> Envoyé: Samedi 12 Septembre 2020 09:11:27 Objet: Re: [mewwts/addict] freeze(), unfreeze(), and nested key support (#123) Hey! Can you split this PR into two where one has the freeze-functionality and another one missing keys? — You are receiving this because you authored the thread. Reply to this email directly, [ #123 (comment) | view it on GitHub ] , or [ https://github.com/notifications/unsubscribe-auth/ACEYIQS5R2TAANRCFNBPCTDSFMNJ7ANCNFSM4M5E4ZMA | unsubscribe ] .

[mewwts]

Thanks @Yves33!

Essentially - remove the nested keys functionality from here (deleted those changes), open another pull request with the nested keys functionality. I typically do this from the terminal, but looks like you might be using the built-in github editor?

[hellocoldworld]

I would love to see the freeze/unfreeze functionality.

[mewwts]

Closing this in favor of #130