Path: csiph.com!usenet.pasdenom.info!aioe.org!news.stack.nl!newsfeed.xs4all.nl!newsfeed4.news.xs4all.nl!xs4all!post2.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 0.005 X-Spam-Evidence: '*H*': 0.99; '*S*': 0.00; 'subject:: [': 0.04; '"the': 0.07; 'skip:\xa0 40': 0.07; 'abstraction': 0.09; 'logic': 0.09; 'cc:addr:python-list': 0.11; '5:30': 0.16; 'bullet': 0.16; 'cc:name:python list': 0.16; 'distinct': 0.16; 'higher-level': 0.16; 'janssen': 0.16; 'lambda': 0.16; 'models,': 0.16; 'subject: \n ': 0.16; 'subject:OOP': 0.16; 'subject:object': 0.16; 'subject:possible': 0.16; 'subject:programming': 0.16; 'subject:type': 0.16; 'url:ps': 0.16; 'valid.': 0.16; 'language': 0.16; 'sender:addr:gmail.com': 0.17; 'wrote:': 0.18; 'wed,': 0.18; 'mechanism': 0.19; 'subject:] ': 0.20; 'seems': 0.21; 'machine': 0.22; 'programming': 0.22; 'cc:addr:gmail.com': 0.22; 'cc:addr:python.org': 0.22; "shouldn't": 0.24; '\xa0if': 0.24; 'cheers,': 0.24; 'cc:no real name:2**0': 0.24; '>': 0.26; 'second': 0.26; 'subject:/': 0.26; 'url:edu': 0.26; 'header:In- Reply-To:1': 0.27; 'idea': 0.28; 'am,': 0.29; 'wonder': 0.29; 'cc:2**2': 0.30; 'programming.': 0.30; 'message- id:@mail.gmail.com': 0.30; 'url:mailman': 0.30; 'getting': 0.31; 'dimensions': 0.31; 'purely': 0.31; 'url:wikipedia': 0.31; 'writes:': 0.31; 'announce': 0.33; 'style': 0.33; 'trouble': 0.34; '"the': 0.34; 'at:': 0.34; 'received:209.85': 0.35; 'possible.': 0.35; 'received:google.com': 0.35; 'building': 0.35; 'there': 0.35; 'picking': 0.36; 'programming,': 0.36; 'url:listinfo': 0.36; 'url:org': 0.36; 'so,': 0.37; 'two': 0.37; 'received:209': 0.37; 'easily': 0.37; '8bit%:4': 0.38; 'skip:& 20': 0.39; 'functional': 0.39; 'pdf': 0.39; 'skip:p 20': 0.39; '8bit%:6': 0.40; 'skip:* 10': 0.61; 'first': 0.61; 'subject:The': 0.64; 'interest': 0.64; 'different': 0.65; 'six': 0.68; 'design.': 0.68; 'skip:w 40': 0.68; 'theoretical': 0.74; 'downloadable': 0.84; 'foundations': 0.84; 'wish.': 0.84; 'calculus': 0.91; 'essence': 0.91; 'mistake': 0.91; 'obtained': 0.96; '2013': 0.98 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:x-received:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; bh=810TzfdmjLoqyw0asJM2zyihpbkrOFX7dQ8MI43ZQXU=; b=y58i+1juLX2W0g5VmkEolaaZLCzPuH5dpgXvyfC5y/82tHGSaHCf+amy2KkZ0Lsxt8 1+N9VliwUb92es8g3lqhd/LNGgvc5mtj1mPwh8AYiTLbcPiB4UvnU0AfFj8+Hi1B/oOA dLd3qPTIXuRccfH6th2P9kK8eNsYwcVEwK0jzEyPY/WDf0VHegRCSUIE+5YV83z08rJP hh6nPWRurhooYrPERNPmZtG4RWOGCtKJANRYuoZqZVwr1/AXK0s4Bd0HIRbrHXp0ksRW O+idB6dER4Rm7DpBSMK1oqEic4n9akcz+HVm0AaN1z24npg1VtVZ9JsXmT4r/sDaX1J5 xnBg== MIME-Version: 1.0 X-Received: by 10.66.88.105 with SMTP id bf9mr8918128pab.175.1366207442981; Wed, 17 Apr 2013 07:04:02 -0700 (PDT) Sender: rishiyur.nikhil@gmail.com In-Reply-To: <20846.27580.375000.899631@gargle.gargle.HOWL> References: <20846.27580.375000.899631@gargle.gargle.HOWL> Date: Wed, 17 Apr 2013 10:04:02 -0400 X-Google-Sender-Auth: GWqhQ4uVP-B-lHhvZy2zzbldgto Subject: Re: [TYPES] The type/object distinction and possible synthesis of OOP and imperative programming languages From: Rishiyur Nikhil To: Uday S Reddy Content-Type: multipart/alternative; boundary=f46d042e0187541b3604da8ef5c5 Cc: types-list@lists.seas.upenn.edu, Python List 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: 131 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1366207448 news.xs4all.nl 2200 [2001:888:2000:d::a6]:47967 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:43761 --f46d042e0187541b3604da8ef5c5 Content-Type: text/plain; charset=ISO-8859-1 > If you have trouble getting hold of "The Essence of Algol", ... There seems to be a downloadable copy at: www.cs.cmu.edu/~crary/819-f09/Reynolds81.ps It's in PostScript, which is easily convertible to PDF if you wish. Nikhil On Wed, Apr 17, 2013 at 5:30 AM, Uday S Reddy wrote: > [ The Types Forum, http://lists.seas.upenn.edu/mailman/listinfo/types-list] > > Mark Janssen writes: > > > From: en.wikipedia.org: Programming_paradigm: > > > > "A programming paradigm is a fundamental style of computer > > programming. There are four main paradigms: object-oriented, > > imperative, functional and declarative. Their foundations are distinct > > models of computation: Turing machine for object-oriented and > > imperative programming, lambda calculus for functional programming, > > and first order logic for logic programming." > > > > While I understand the interest in purely theoretical models, I wonder > > two things: 1) Are these distinct models of computation valid? And, > > 2) If so, shouldn't a theory of types announce what model of > > computation they are working from? > > These distinctions are not fully valid. > > - Functional programming, logic programming and imperative programming are > three different *computational mechanisms*. > > - Object-orientation and abstract data types are two different ways of > building higher-level *abstractions*. > > The authors of this paragraph did not understand that computational > mechanisms and higher-level abstractions are separate, orthogonal > dimensions > in programming language design. All six combinations, obtained by picking > a > computational mechanism from the first bullet and an abstraction mechanism > from the second bullet, are possible. It is a mistake to put > object-orientation in the first bullet. Their idea of "paradigm" is vague > and ill-defined. > > Cheers, > Uday Reddy > --f46d042e0187541b3604da8ef5c5 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable

> =A0 =A0If you have trouble getting hold of &quo= t;The Essence of Algol", ...

There seems to be a down= loadable copy at:


It's in PostScript, which is easily convertible= to PDF if you wish.
Nikhil


On Wed= , Apr 17, 2013 at 5:30 AM, Uday S Reddy <u.s.reddy@cs.bham.ac.uk= > wrote:
[ The Types Forum, http://lists.seas.upenn.edu/mailman/listinfo/types-list ]

Mark Janssen writes:

> From: =A0en.wiki= pedia.org: Programming_paradigm:
>
> "A programming paradigm is a fundamental style of computer
> programming. There are four main paradigms: object-oriented,
> imperative, functional and declarative. Their foundations are distinct=
> models of computation: Turing machine for object-oriented and
> imperative programming, lambda calculus for functional programming, > and first order logic for logic programming."
>
> While I understand the interest in purely theoretical models, I wonder=
> two things: =A01) =A0Are these distinct models of computation valid? = =A0And,
> 2) If so, shouldn't a theory of types announce what model of
> computation they are working from?

These distinctions are not fully valid.

- Functional programming, logic programming and imperative programming are<= br> three different *computational mechanisms*.

- Object-orientation and abstract data types are two different ways of
building higher-level *abstractions*.

The authors of this paragraph did not understand that computational
mechanisms and higher-level abstractions are separate, orthogonal dimension= s
in programming language design. =A0All six combinations, obtained by pickin= g a
computational mechanism from the first bullet and an abstraction mechanism<= br> from the second bullet, are possible. =A0It is a mistake to put
object-orientation in the first bullet. =A0Their idea of "paradigm&quo= t; is vague
and ill-defined.

Cheers,
Uday Reddy

--f46d042e0187541b3604da8ef5c5--