How to list tasks from your project

rake -T

• Use Rakefile for tasks that operate on the plugin’s source files, such as special testing or documentation. These must be run from the plugin’s directory.
• Use tasks/*.rake for tasks that are part of the development or deployment of the application in which the plugin is installed. These will be shown in the output of rake ,ÄìT, the list of all Rake tasks for this application.
  
  
  
  

How to extend a class

class Symbol
  def %(arg)
    ...
  end
end

The above code does what you need, but leaves no hint that you've made a change to Symbol. An alternative solution is to define a module and include that module in Symbol.

module SymbolExtension
  def %(arg)
    ...
  end
end

Symbol.send :include, SymbolExtension

Granted, this isn't a huge hint, but if you check Symbol.ancestors you'll find the following list.

Symbol
SymbolExtension
Object
Kernel

extracted from: http://blog.jayfields.com/2007/01/class-reopening-hints.html

plugins on rails 3.0

How to install it?

rails plugin install URL

How to remove it?

rails plugin remove plugin_name
How to create your own plugin?
rails generate plugin my_plugin
The files that are required are:
init.rb
and directory in the plugin called lib

A few special variables are available to your code in init.rb:
name The name of your plugin ('my_plugin' in our simple example).
path The directory in which the plugin exists, which is useful in case you need to read or write nonstandard files in your plugin’s directory. 
config The configuration object created in environment.rb. (See Chapter 1, “Rails Environments and Configuration,” as well as the online API docs for Rails::Configuration to learn more about what’s available via config.)

How to setup your Git environment from scratch

SERVER SIDE
sudo apt-get install git-core git-doc gitweb git-gui gitk git-email
git-svn git-daemon-run
git init
git add .
git commit
git clone --bare ./menucook menucook.git

get the repo
git clone ssh://inguansoftsvn/home/inguanzo/depo/menucook.git

How to create a remote branch
git push origin origin:refs/heads/web

workflow to deploy into the server
git rebase origin/web

prompt for snowleopard:
parse_git_branch() {
  git branch 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/(\1)/'
}
PS1="\[\e[01;31m\]\w \$(parse_git_branch): \[\e[00m\]"

prompt for linux:
if [ "\$(type -t __git_ps1)" ]; then
    PS1="\w \$(__git_ps1 '(%s)$ ')"
fi

clean apps from iPhone simulator

to clear out old iPhone simulator's applications :

• delete the folder called iPhone Simulator from the Application Support folder contained in your home directory's Library folder. 
• or selecting iOS Simulator --> Reset Content and Settings...

eval is evil

eval for any objective should not be used, even for parsing JSON

passing strings to setInterval(), setTimeout(), and the Function() constructor is, for the most part, similar to using eval()

dynamic access to constants on ruby

How to verify if the constant is available?
self.const_defined?('DEFAULT_VALUES')

How to call for it: simple way:     MyClass::CONSTANT
Dynamic cool way: MyClass.const_get("CONSTANT")