by Keven Lin

Sep 03

Ruby include, extend, require and load explained

The Ruby ‘include’ statement references to a named module; it appends features of a module into classes or other modules.  

‘extend’ adds the features of a module to one instance (object) at run-time

‘require’ is used for loading nonmodule Ruby sources and binaries.  ’require’ is similar to a ‘load’ ,but it will not load a file if it has already been loaded.

‘include’ and ‘require’ are essentially unrelated.  You may need to do a require follow by an include to use some externally stored module.

Aug 12

Git - revert / undo local modifications

To undo local modification to file

git checkout -f /path/to/file

To revert a recent commit
git reset HEAD~

Good reference for Git material: Kernel Hackers’ Guide to git

Aug 05

[video]

Aug 03

approach on product design -

Paul Buchheit:

What is the humble approach to product design? Pay attention. Notice which things are working and which aren’t. Experiment and iterate. Question your assumptions. Remember that you are wrong about a lot of things. Watch for the signals. Lose your technical and design snobbery. Whatever works, works.

Jul 18

Restart Apache w/ mod_rails on Leopard

sudo apachectl restart

Hackers discuss about tradings -

two of my favorite subjects

Jul 11

“The only true wisdom is in knowing you know nothing” — via Paul Buchheit

Jul 09

my current interests

programming languages, web frameworks, non-relational db, stock trading strategies, collective intelligence, minimalism

“Remember that time is money” — Ben Franklin, 1748 (Advice to a young tradesman)

Blowing Up -

on Nassim Taleb by Malcom Gladwell - two of my current favorite storytellers

“he buys options on both sides, on the possibility of the market moving both up and down. And he doesn’t bet on minor fluctuations in the market. Why bother? If everyone else is vastly underestimating the possibility of rare events, then an option on G.M. at, say, forty dollars is going to be undervalued. So Taleb buys out-of-the-money options by the truckload. He buys them for hundreds of different stocks, and if they expire before he gets to use them he simply buys more.”

Jul 08

Questions to ask when launching new product

from http://evhead.com/2007/12/how-to-evaluate-new-product-idea.asp

* How difficult will it be to launch a worthwhile version 1.0?
* Is it clear why people should use it?
* How much value can you ultimately deliver? 
* How many people may ultimately use it?
* How will people learn about your product?
* How hard will it be to extract the money?
* Do you really want it to exist in the world?

Hacker News Algorithm

(p - 1) / (t 2)^1.5

where p = points and t = age in hours

http://news.ycombinator.com/item?id=231209

“

Steve Jobs’s ability to focus in on a few things that count, get people who get user interface right and market things as revolutionary are amazing things.

This time somehow he has applied his talents in getting a better licensing deal than anyone else has gotten for music.