wess

CREATE EXTENSION IF NOT EXISTS plpgsql;

CREATE TABLE doc_store (
  key text PRIMARY KEY,
  value json
);

CREATE OR REPLACE FUNCTION insert_key_value(p_key text, p_value json)
RETURNS void AS $$
BEGIN

halfelf

https://web.archive.org/web/20110219163448/http://howtohft.wordpress.com/2011/02/15/how-to-build-a-fast-limit-order-book/

The response to my first few posts has been much larger than I’d imagined and I’d like to thank everyone for the encouragement.

If you’re interested in building a trading system I recommend first reading my previous post on general ideas to keep in mind.

My first really technical post will be on how to build a limit order book, probably the single most important component of a trading system. Because the data structure chosen to represent the limit order book will be the primary source of market information for trading models, it is important to make it both absolutely correct and extremely fast.

To give some idea of the data volumes, the Nasdaq TotalView ITCH feed, which is every event in every instrument traded on the Nasdaq, can have data rates of 20+ gigabytes/day with spikes of 3 megabytes/second or more. The individual messages average about 20 bytes each so this means handling

ZipCPU

<student> Yes I am 
<ZipCPU> You asked a question on ##verilog some time ago, and then left before I noticed and answered the question.
<ZipCPU> I wanted to make certain you were on line before I commented on any of your issues.
<ZipCPU> Further, because the ##fpga discussion is struggling to handle about 3 topics at once, I thought it might be simpler to leave the discussion channel.
<student> Yea that's right, I left before receiving any answers, I waited a lot but none answered.
<ZipCPU> You were asking some fascinating questions on ##fpga.
<ZipCPU> May I try my hand at answering any of them?
<student> Yea sure, I would be too thankful for that as I'm starting my way in digital design and I have multiple issues that I didn't find answer on edaboard forums, and IRC as well! 
<ZipCPU> So ... I started digital design in earnest almost two years ago.  In many ways, I'm a newbie.  On the other hand, I do have a graduate degree in computer engineering, so ... I might know a thing or two ...
<ZipCPU> At one time,

jeremytregunna

How to Symbolize OSX Crash Logs

Unfortunately, xcode does not yet have support for importing OSX crash logs and symbolizing them. Therefore, you must use the command line and a little bit of manual work.

1. Find your dSYM file.
   1. Assuming you are using xcode's archive functionality, open the Organizer window from the Window menu.
   2. Click the Archives tab.
   3. Right click on the appropriate build and select Show in Finder.
   4. When Finder opens, right click on the selected archive and select Show Package Contents.
   5. Navigate to the dSYM directory and copy the appropriate dSYM file to a temporary directory.
2. Then navigate to Products, then Applications, and copy the app file to the same temporary directory.

ryanflorence

Turning Off Github Issues

My friend Michael Jackson turned off github issues on one of his smaller projects. It got me thinking...

Maintainers getting burned out is a problem. Not just for the users of a project but the mental health of the maintainer. It's a big deal for both parties. Consumers want great tools, maintainers want to create them, but maintainers don't want to be L1 tech support, that's why they

gist:8a163db3f7f3d81d5296

Your goals are to reduce the number of things that you have to keep in your head at any given moment, and to rely as little as possible on your own ability to consistently do things right.
If you make a thing immutable ('let' in swift), you never have to think about what happens if it changes, or what other parts of the code you'll effect if you change it.
If you split complex functions into several smaller functions that only interact by passing arguments or getting return values, then you limit the amount of code you need to consider when hunting for a bug, and you can test each small piece separately.
If you understand what things must be true in your code (aka invariants, for example "a person's age must be greater than 0"), and either provide no function that can cause them to be untrue, or check and crash immediately when they're untrue, then you don't have to debug issues caused by incorrect assumptions.
If you remove possibilities (for example, Swift removes the possibility of things being nil unless 

angelolloqui

@interface AGCommand : NSObject
 
@property(nonatomic, weak) UIResponder *firingObject;
@property(nonatomic, readonly) SEL action;
 
+ (instancetype)command;
 
@end

txus

For language developers on the Rubinius platform, the APIs to the Rubinius generator and other compiler parts are generally very smooth and easy to use. An exception to this is when trying to generate a function/closure. Messing with the low-level APIs turns out to be unwieldy, as they tend to expose quite a lot of detail about Ruby-specific semantics.

The goal of this proposal is to provide a higher-level API optimized for a more general use case.

The file ast.rb contains the user code, and the file new_api.rb contains the support code to make it work (what would end up being implemented in some rubinius gem).

coffeemug

After spending the better part of the month implementing date support
in RethinkDB, Mike Lucy sent the team the following e-mail. It would
have been funny, if it didn't cause thousands of programmers so much
pain. Read it, laugh, and weep!

-----

So, it turns out that we're only going to support dates between the
year 1400 and the year 10000 (inclusive), because that's what boost
supports.

brentsimmons

@implementation UITextView (RSExtras)


static BOOL stringCharacterIsAllowedAsPartOfLink(NSString *s) {

    /*[s length] is assumed to be 0 or 1. s may be nil.
     Totally not a strict check.*/

    if (s == nil || [s length] < 1)
        return NO;