rake-0.8.3.rdoc   [plain text]


= Rake 0.8.3 Released

Rake version 0.8.3 is a bug-fix release of rake.

== Changes

=== Bug Fixes in Version 0.8.3

* Enhanced the system directory detection in windows. We now check
  HOMEDRIVE/HOMEPATH and USERPROFILE if APPDATA isn't found. (Patch
  supplied by James Tucker). Rake no long aborts if it can't find the
  directory.

* Added fix to handle ruby installations in directories with spaces in
  their name.  

== What is Rake

Rake is a build tool similar to the make program in many ways. But
instead of cryptic make recipes, Rake uses standard Ruby code to
declare tasks and dependencies. You have the full power of a modern
scripting language built right into your build tool.

== Availability

The easiest way to get and install rake is via RubyGems ...

  gem install rake    (you may need root/admin privileges)

Otherwise, you can get it from the more traditional places:

Home Page:: http://rake.rubyforge.org/
Download::  http://rubyforge.org/project/showfiles.php?group_id=50

== Task Argument Examples

Prior to version 0.8.0, rake was only able to handle command line
arguments of the form NAME=VALUE that were passed into Rake via the
ENV hash.  Many folks had asked for some kind of simple command line
arguments, perhaps using "--" to separate regular task names from
argument values on the command line.  The problem is that there was no
easy way to associate positional arguments on the command line with
different tasks.  Suppose both tasks :a and :b expect a command line
argument: does the first value go with :a?  What if :b is run first?
Should it then get the first command line argument.

Rake 0.8.0 solves this problem by explicitly passing values directly
to the tasks that need them.  For example, if I had a release task
that required a version number, I could say:

   rake release[0.8.3]

And the string "0.8.3" will be passed to the :release task.  Multiple
arguments can be passed by separating them with a comma, for example:

   rake name[john,doe]

Just a few words of caution.  The rake task name and its arguments
need to be a single command line argument to rake.  This generally
means no spaces.  If spaces are needed, then the entire rake +
argument string should be quoted.  Something like this:

   rake "name[billy bob, smith]"

(Quoting rules vary between operating systems and shells, so make sure
you consult the proper docs for your OS/shell).

=== Tasks that Expect Parameters

Parameters are only given to tasks that are setup to expect them.  In
order to handle named parameters, the task declaration syntax for
tasks has been extended slightly.

For example, a task that needs a first name and last name might be
declared as:

   task :name, :first_name, :last_name

The first argument is still the name of the task (:name in this case).
The next to argumements are the names of the parameters expected by
:name (:first_name and :last_name in the example).

To access the values of the paramters, the block defining the task
behaviour can now accept a second parameter:

   task :name, :first_name, :last_name do |t, args|
     puts "First name is #{args.first_name}"
     puts "Last  name is #{args.last_name}"
   end

The first argument of the block "t" is always bound to the current
task object.  The second argument "args" is an open-struct like object
that allows access to the task arguments.  Extra command line
arguments to a task are ignored.  Missing command line arguments are
given the nil value.

== Thanks

As usual, it was input from users that drove a alot of these changes. The
following people either contributed patches, made suggestions or made
otherwise helpful comments.  Thanks to ...

* Edwin Pratomo
* Gavin Stark
* Adam Q. Salter
* Adam Majer
* Emanuel Indermühle
* Ittay Dror
* Bheeshmar Redheendran (for spending an afternoon with me debugging
  windows issues)

-- Jim Weirich