| 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

I Want To Be A Redneck!; Reverse Racism; The Lost Art Of Nomography; IBM Data Center (Photo); Interesting Account Of Gamma Hack; The Most Interesting Audiophile In The World; How did the first world war actually end?; Ky - Restaurant Santiago; The Black Dork Lives!; The UN Requires Unaninmous Decisions; LPIR - Steganography in Practice; How I Am 6; Clear Explanation of Verizon / Level 3 / Netflix; Teenage Girls; Formalising NSA Attacks; Switching Brakes (Tektro Hydraulic); Naim NAP 100 (Power Amp); AKG 550 First Impressions; Facebook manipulates emotions (no really); Map Reduce "No Longer Used" At Google; Removing RAID metadata; New Bike (Good Bike Shop, Santiago Chile); Removing APE Tags in Linux; Compiling Python 3.0 With GCC 4.8; Maven is Amazing; Generating Docs from a GitHub Wiki; Modular Shelves; Bash Best Practices; Good Emergency Gasfiter (Santiago, Chile); Readings in Recent Architecture; Roger Casement; Integrated Information Theory (Or Not); Possibly undefined macro AC_ENABLE_SHARED; Update on Charges; Sunburst Visualisation; Spectral Embeddings (Distances -> Coordinates); Introduction to Causality; Filtering To Help Colour-Blindness; ASUS 1015E-DS02 Too; Ready Player One; Writing Clear, Fast Julia Code; List of LatAm Novels; Running (for women); Building a Jenkins Plugin and a Jar (for Command Line use); Headphone Test Recordings; Causal Consistency; The Quest for Randomness; Chat Wars; 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)

© 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