Saturday, September 22, 2012

Easing functions

Sunday, September 2, 2012

RVM cheat sheets


RVM home page:

Install RVM


bash -s stable < <(curl -s \

Update RVM

    rvm get stable

In case of problems try first with development version
(maybe it's already fixed):

    rvm get head

Very old installations might not support those update methods, just run the
installer and reopen your terminal.

List known rubies

    rvm list known

Install Ruby dependencies

Follow instructions from:

    rvm requirements

Install Ruby

    rvm install 1.9.3                # Latest known patch level
    rvm install 1.9.3 -j 3           # Parallel compile, set to # of CPU cores
    rvm install 1.9.3 --patch falcon # Use a patch (falcon for performance)
    rvm install 1.9.2-p318           # Patchlevel 318
    rvm install rbx --1.9            # Rubinius with 1.9 mode set as default

List all rubies and gemsets

    rvm list         # List rubies only
    rvm list gemsets # List rubies and gemsets
    rvm gemset list  # List gemsets for current ruby

Selecting Ruby for work

    rvm system                 # For system ruby, with fallback to default 
    rvm use jruby              # For current session only
    rvm use --default 1.9.3    # For current and new sessions
    rvm use --ruby-version rbx # For current session and this project

RVM will automatically use a ruby and gemset when you `cd` to a project

Read more on project files:


Using ruby and gems

After selecting Ruby work as usual:

    ruby -v
    gem install haml

Temporarily selecting another Ruby or gemset

    rvm 1.8.7 do gem install rspec      # in the given ruby
    rvm 1.8.7,1.9.2 do gem install haml # in this two rubies
    rvm @global do gem install gist     # in @global gemset of current ruby


RVM by default allows creating multiple environments for one ruby - called

Gemsets can be specified together with ruby name using gemsets separator(@):

- ruby-1.9.3-p125@my-project

During installation of Ruby, RVM creates two gemsets:

- default - automatically selected when no @gemset specified: rvm use 1.9.3
- global  - super gemset, inherited by all other gemsets for the given ruby

Working with gemsets:

    rvm use 1.8.7                   # use the ruby to manage gemsets for
    rvm gemset create project_name  # create a gemset
    rvm gemset use project_name     # use a gemset in this ruby
    rvm gemset list                 # list gemsets in this ruby
    rvm gemset delete project_name  # delete a gemset
    rvm 1.9.1@other_project_name    # use another ruby and gemset
    rvm 1.9.3@_project --create     # use and create gemset if not existing

Install RVM for all users

Discouraged; make sure to read

More help ?

A lot of resources is available:

- in your terminal: `rvm help`
- IRC #rvm @ freenode -

Installing MongoDB with Homebrew

Installation of mysql and mongodb with brew sometimes could end with an access error, for example:

Error: Permission denied - /usr/local/var/log/mongodb

Actually, there is no proper decision yet, so the short term solution might be the following:

ls -al /usr/local/bin/brew #confirm brew ownership

sudo chown root:wheel /usr/local/bin/brew
sudo brew install mongodb
sudo chown <your user>:<your group> /usr/local/bin/brew  #revert ownership

Powered by Blogger.