Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!newsfeed.xs4all.nl!newsfeed2a.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.015 X-Spam-Evidence: '*H*': 0.97; '*S*': 0.00; 'assignment': 0.07; 'tries': 0.07; 'filename': 0.09; 'cc:addr:python-list': 0.11; 'def': 0.12; 'assignment.': 0.16; 'dict': 0.16; 'from:addr:rosuav': 0.16; 'from:name:chris angelico': 0.16; 'notation': 0.16; 'subject:Object': 0.16; 'typeerror:': 0.16; 'userdict': 0.16; 'wrote:': 0.18; 'trying': 0.19; 'thu,': 0.19; 'written': 0.21; 'help.': 0.21; 'feb': 0.22; 'cc:addr:python.org': 0.22; 'simpler': 0.24; 'cc:2**0': 0.24; "i've": 0.25; 'header:In- Reply-To:1': 0.27; 'idea': 0.28; 'specifically': 0.29; 'am,': 0.29; "doesn't": 0.30; 'message-id:@mail.gmail.com': 0.30; "i'm": 0.30; '13,': 0.31; 'though.': 0.31; 'class': 0.32; 'skip:_ 10': 0.34; 'problem': 0.35; "can't": 0.35; 'skip:u 20': 0.35; 'but': 0.35; 'received:google.com': 0.35; 'really': 0.36; 'subject:Simple': 0.36; 'detail': 0.37; 'handle': 0.38; 'rather': 0.38; 'that,': 0.38; 'itself': 0.39; 'sure': 0.39; "you're": 0.61; "you've": 0.63; 'more': 0.64; 'occur': 0.65; 'of:': 0.68; 'gain': 0.79; 'actually,': 0.84; 'dict,': 0.84; 'dict.': 0.84; 'to:none': 0.92 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:cc :content-type; bh=bflJKp1BnNO8RItcKlhcFbHgpG3BGgeZbOOhzDKdg4k=; b=vrOWMGvJcH/XYCStJn4LIry2iVg8MFFch8aIv95HiYiFyGX1eSyxFp+hPuZTs2Bpq1 75+247GnWe7tm/GZrZQro9/yFkNi70RJitd1GH1AVDOIdPlmTFVhERDDYmCaFD0z2ACD d4ChAsxLemLG8LjxMdJrr3u5Xajqni+uwWv+sAcisWC8qHx8bYCWQqFJ44xGm1UE54Dh HPPJDcKQcHbzrt6Hg+04JuZXaaSxJX0opI8cGCdl59yAuDdrbhv+8DVpR97yXei9bkZL ndxRnY6B9XblEiJ2HXe+FyQIoum/SgbLlRZOtNCxoKXVK++pn+0NL4BFfqdlMdqJciNB f0Og== MIME-Version: 1.0 X-Received: by 10.68.200.74 with SMTP id jq10mr6210342pbc.169.1392240396303; Wed, 12 Feb 2014 13:26:36 -0800 (PST) In-Reply-To: References: Date: Thu, 13 Feb 2014 08:26:36 +1100 Subject: Re: Simple Object assignment giving me errors From: Chris Angelico Cc: "python-list@python.org" Content-Type: text/plain; charset=UTF-8 X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 27 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1392240405 news.xs4all.nl 2850 [2001:888:2000:d::a6]:46277 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:66093 On Thu, Feb 13, 2014 at 8:18 AM, Nir wrote: > class FileInfo(UserDict): > def __init__(self, filename=None): > UserDict.__init__(self) > self["name"] = filename > > I get a TypeError: 'FileInfo' object doesn't support item assignment . > > Am I missing something? You can't use square-brackets notation like that, unless you've written your class specifically to handle it. More likely, what you want is one of: self.name = filename self.dict["name"] = filename Also, the same problem will occur with the UserDict, which tries to update itself rather than its dict. Actually, a simpler solution might be to have UserDict inherit from dict. I'm not sure what you're trying to achieve here; more detail would help. But if UserDict really is a dict, then you can call self.update, and you can use square-brackets item assignment. I've no idea what you'd gain over just using a dict though. ChrisA