| Andrew Cooke | Contents | Latest | RSS | Twitter | Previous | Next

C[omp]ute

Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

Personal Projects

Lepl parser for Python.

Colorless Green.

Photography around Santiago.

SVG experiment.

Professional Portfolio

Calibration of seismometers.

Data access via web services.

Cache rewrite.

Extending OpenSSH.

Last 100 entries

Real-life Financial Co Without ACID Database...; Flexible Muscle-Based Locomotion for Bipedal Creatures; SQL Performance Explained; The Little Manual of API Design; Multiple Word Sizes; CRC - Next Steps; FizzBuzz; Update on CRCs; Decent Links / Discussion Community; Automated Reasoning About LLVM Optimizations and Undefined Behavior; A Painless Guide To CRC Error Detection Algorithms; Tests in Julia; Dave Eggers: what's so funny about peace, love and Starship?; Cello - High Level C Programming; autoreconf needs tar; Will Self Goes To Heathrow; Top 5 BioInformatics Papers; Vasovagal Response; Good Food in Vina; Chilean Drug Criminals Use Subsitution Cipher; Adrenaline; Stiglitz on the Impact of Technology; Why Not; How I Am 5; Lenovo X240 OpenSuse 13.1; NSA and GCHQ - Psychological Trolls; Finite Fields in Julia (Defining Your Own Number Type); Julian Assange; Starting Qemu on OpenSuse; Noisy GAs/TMs; Venezuela; Reinstalling GRUB with EFI; Instructions For Disabling KDE Indexing; Evolving Speakers; Changing Salt Size in Simple Crypt 3.0.0; Logarithmic Map (Moved); More Info; Words Found in Voynich Manuscript; An Inventory Of 3D Space-Filling Curves; Foxes Using Magnetic Fields To Hunt; 5 Rounds RC5 No Rotation; JP Morgan and Madoff; Ori - Secure, Distributed File System; Physical Unclonable Functions (PUFs); Prejudice on Reddit; Recursion OK; Optimizing Julia Code; Cash Handouts in Brazil; Couple Nice Music Videos; It Also Works!; Adaptive Plaintext; It Works!; RC5 Without Rotation (2); 8 Years...; Attack Against Encrypted Linux Disks; Pushing Back On NSA At IETF; Summary of Experimental Ethics; Very Good Talk On Security, Snowden; Locusts are Grasshoppers!; Vagrant (OpenSuse and IDEs); Interesting Take On Mandela's Context; Haskell Cabal O(n^2) / O(n) Fix; How I Am 4; Chilean Charity Supporting Women; Doing SSH right; Festival of Urban Intervention; Neat Idea - Wormholes Provide Entanglement; And a Link....; Simple Encryption for Python 2.7; OpenSuse 13.1 Is Better!; Little Gain...; More Details on Technofull Damage; Palmrest Cracked Too....; Tecnofull (Lenovo Support) Is Fucking Useless; The Neuroscientist Who Discovered He Was a Psychopath; Interpolating Polynomials; Bottlehead Crack as Pre-amp; Ooops K702!; Bottlehead Crack, AKG K701; Breaking RC5 Without Rotation; Great post thank you; Big Balls of Mud; Phabricator - Tools for working together; Amazing Julia RC5 Code Parameterized By Word Size; Chi-Square Can Be Two-Sided; Why Do Brits Accept Surveillance?; Statistics Done Wrong; Mesas Trape from Bravo; European Report on Crypto Primitives and Protocols; Interesting Omissions; Oryx And Crake (Margaret Atwood); Music and Theory; My Arduino Programs; Elliptic Curve Crypto; Re: Licensing Interpreted Code; Licensing Interpreted Code; ASUS 1015E-DS03 OpenSuse 12.3 SSD; translating lettuce feature files into stub steps files; Re: translating lettuce feature files into stub steps files; A Tale of Two Psychiatrists; The Real Reason the Poor Go Without Bank Accounts

© 2006-2013 Andrew Cooke (site) / post authors (content).

Algebraic ABCs - A DSL for Types in Python

From: andrew cooke <andrew@...>

Date: Fri, 29 Apr 2011 22:28:21 -0300

This is a draft, and the pytyp library it describes is not the one available
for download (although it is in hg on Google code), but I wanted to put it out
there in case anyone had any comments (which would be MUCH appreciated)

I think it's pretty cool.  It's a DSL for Python that integrates with ABCs to
extend Python's types.  Some examples:

    >>> isinstance(5, Or(int, str))
    True
    >>> isinstance("five", Or(int, str))
    True

    >>> @checked
    ... def int_list_len(s:[int]) -> int:
    ...     return len(s)
    >>> int_list_len([1,2,3])
    3
    >>> int_list_len('abc')
    Traceback (most recent call last):
      ...
    TypeError: Type Seq(int) inconsistent with 'abc'.

    >>> class Foo:
    ...     def __init__(self, x):
    ... 	self.x = x
    >>> ifoo = Foo(1)
    >>> sfoo = Foo('one')
    >>> assert isinstance(ifoo, Foo)
    >>> assert isinstance(sfoo, Cls(Foo))
    >>> assert isinstance(ifoo, And(Foo, Atr(x=int)))
    >>> assert not isinstance(sfoo, And(Foo, Atr(x=int)))

Anyway, the paper is at http://www.acooke.org/pytyp.pdf

Andrew

PS If you are reading this post in the future (woot!  flying cars!) then I may
have replaced the link with a more up-to-date version, and updated the
library, of course.

Updated Python Types Draft

From: andrew cooke <andrew@...>

Date: Fri, 6 May 2011 21:49:18 -0300

I've just posted an updated draft of the Python Types paper to the same link
http://www.acooke.org/pytyp.pdf

This has a bunch of (I hope) improvements:

  - It tries to avoid confusion by avoiding terms that sounds like
    previously-existing terms for ideas that are only vaguely related.

  - It is clearer about what it doesn't do (but still has some way to go).

  - I'm starting to add multimethods.

I'm hoping that the sections before (and excluding) Conclusions are now pretty
much final (except that I need to implement and document more control over
exceptions for back-tracking).

Andrew

Maybe not Multimethods

From: andrew cooke <andrew@...>

Date: Fri, 6 May 2011 21:52:59 -0300

Ironically, as I read what I just posted, I notice that what I am calling
mutlimethods are not really *methods* of the types used in dispatch.  So I
will need to fix that too...

Sorry,
Andrew

Comment on this post