I just finished my "Learn Ruby" talk for the programmers here at work. (Game programmers, strong in C/C++).
I flew through a massive amount of stuff.. leaving continuations and metaprogramming on the table for another day. I managed to get it done just over my goal of 90 minutes (maybe 100).
I found that the programmers who'd worked in dynamic languages previously, through a University course or otherwise, followed along pretty well. Those without that experience dazed out once we got into things like lambdas.
Overall though, I'm satisfied.
I did my presentation in HTML generated from ERB. I just set my browser to full-screen -- it worked pretty well. I've posted both the ERB and HTML files at: http://www.waits.net/~swaits/LearnRubyTalk/
I'd very much like to improve the document, so any feedback is appreciated. It also might be useful to others in my situation (teaching Ruby to programmers).
I just finished my "Learn Ruby" talk for the programmers here at work. (Game programmers, strong in C/C++).
I flew through a massive amount of stuff.. leaving continuations and metaprogramming on the table for another day. I managed to get it done just over my goal of 90 minutes (maybe 100).
I found that the programmers who'd worked in dynamic languages previously, through a University course or otherwise, followed along pretty well. Those without that experience dazed out once we got into things like lambdas.
Overall though, I'm satisfied.
I did my presentation in HTML generated from ERB. I just set my browser to full-screen -- it worked pretty well. I've posted both the ERB and HTML files at: http://www.waits.net/~swaits/LearnRubyTalk/
I'd very much like to improve the document, so any feedback is appreciated. It also might be useful to others in my situation (teaching Ruby to programmers).
--Steve
--
knowledge is important, but the much more important is the use toward which it
is put. this depends on the heart and mine the one who uses it.
- h.h. the 14th dali lama
I'd very much like to improve the document, so any feedback is
appreciated. It also might be useful to others in my situation
(teaching Ruby to programmers).
--Steve
Looks great, Steve. Thanks for publicizing it.
I'm wondering, how much confusion was there over symbols? Were the
dynamic-language folks more comfortable with symbols than the others?
This is one thing I sometimes find is hard to explain to someone who is
new to Ruby.
"Little Miss Mixins, you are a skanky friend-with-benefits."
···
On 3/8/06, Stephen Waits <steve@waits.net> wrote:
I just finished my "Learn Ruby" talk for the programmers here at work.
(Game programmers, strong in C/C++).
I flew through a massive amount of stuff.. leaving continuations and
metaprogramming on the table for another day. I managed to get it done
just over my goal of 90 minutes (maybe 100).
I found that the programmers who'd worked in dynamic languages
previously, through a University course or otherwise, followed along
pretty well. Those without that experience dazed out once we got into
things like lambdas.
Overall though, I'm satisfied.
I did my presentation in HTML generated from ERB. I just set my browser
to full-screen -- it worked pretty well. I've posted both the ERB and
HTML files at: http://www.waits.net/~swaits/LearnRubyTalk/
I'd very much like to improve the document, so any feedback is
appreciated. It also might be useful to others in my situation
(teaching Ruby to programmers).
--
R. Mark Volkmann
Partner, Object Computing, Inc.
I just finished my "Learn Ruby" talk for the programmers here at work.
(Game programmers, strong in C/C++).
...
I'd very much like to improve the document, so any feedback is
appreciated. It also might be useful to others in my situation (teaching
Ruby to programmers).
Your section on control structures is a little broken. You have "loop do ...
end while ...". The while condition will only be evaluated once (so it's
equivalent to "if"), and if true "loop" will repeat the block forever. What
did you intend this example to do?
I'd very much like to improve the document, so any feedback is
appreciated. It also might be useful to others in my situation
(teaching Ruby to programmers).
I only read the first 20% or so (for lack of time at the moment), but I
have to say that it looks great, Steve. I've already spurled it,
and will be recommending it to people when they ask about Ruby. It is
extremely heavy on examples and snippets, which I think is a wonderful
thing. Any documentation about programming which has few or no examples
is an exercise in anguish and frustration (can you say perldoc?).
Again, good job. Look forward to future revisions.
I'm wondering, how much confusion was there over symbols? Were the dynamic-language folks more comfortable with symbols than the others? This is one thing I sometimes find is hard to explain to someone who is new to Ruby.
I explained it to them that as a programmer we'd basically use symbols very similarly to how we use enums in C/C++. I showed how they're commonly used as keys in hashes.
I explained that each symbol has a unique ID, and that Ruby uses symbols to look stuff up within its own system. I believe I had given them several ".send(:symbol)" examples at that point.
I showed them :symbol.to_i, and :symbol.class too.
I *think* they understood it. I didn't notice any difference between the dynamic experienced and the rest.
Oh yikes! It's just a poor example and it's what I get for working on this in the wee hours of the morning.
I updated it. Thanks for catching that Dave!
--Steve
···
On Mar 8, 2006, at 7:03 PM, Dave Burt wrote:
Your section on control structures is a little broken. You have "loop do ...
end while ...". The while condition will only be evaluated once (so it's
equivalent to "if"), and if true "loop" will repeat the block forever. What
did you intend this example to do?
I explained that each symbol has a unique ID, and that Ruby uses symbols
to look stuff up within its own system. I believe I had given them
several ".send(:symbol)" examples at that point.
And it's much better than the "it's an immutable string" explanation,
which I've found to be just a rats nest of problems.
Enums are another good analogy. But in C++/C# enums are typed so you
know the client gave you a valid value. The only way I can see to
enforce this in Ruby is to create a constant array of the valid symbols
and then make sure what they passed me is in the array:
class HockeyGear
BuyableGear = [ :stick, :helmet, :skates ]
def self.buy_something(gear)
if (!BuyableGear.include?(gear))
return nil
end
Somehow I feel this is pretty un-rubylike, to have to have that if
statement in front of every method. Any idea if there's a more
ruby-like way to have enum-like behavior?
I just finished my "Learn Ruby" talk for the programmers here at work.
(Game programmers, strong in C/C++).
...
I'd very much like to improve the document, so any feedback is
appreciated. It also might be useful to others in my situation (teaching
Ruby to programmers).
While we're on errata, the @instance_var in the section on Variables may be
misleading to newcomers. In that scope, it's "one per instance" of the class
Dismissed, and there will only be one of these. It's only in an instance
method (e.g. initialize) that you will have a variable for each instance of
the class. Again in the Idiomatic Ruby section.
class Foo @instance_var = 0 # belongs to Foo itself
def bar @instance_var = 0 # one per instance
end
end
Mixins:
LessThanOrEqualComparable#>(other) should be "not self < other and not self
== other"
= should probably be not self < other
Also, I'm surprised you didn't cover Range in the core classes. All you have
to do is
r = 1..5 #=> 1..5
r.class #=> Range
r.each {|i| puts i }
Under Everything is an Object, you didn't use is_a? kind_of? or superclass,
and you didn't actually show that anything was an object. You did show
everything has a class, and that Class is a Class. In particular, this is
not implied by Object.class #=> Class. You can demonstrate it like this:
"foo".kind_of? Object #=> true
Class.kind_of? Object #=> true
Person.superclass #=> Object
Class.superclass #=> Module
Class.superclass.superclass #=> Object
I explained that each symbol has a unique ID, and that Ruby uses symbols
to look stuff up within its own system. I believe I had given them
several ".send(:symbol)" examples at that point.
And it's much better than the "it's an immutable string" explanation,
which I've found to be just a rats nest of problems.
Enums are another good analogy. But in C++/C# enums are typed so you
know the client gave you a valid value. The only way I can see to
enforce this in Ruby is to create a constant array of the valid symbols
and then make sure what they passed me is in the array:
Enums are typed in C++, to a certain extent (better than C anyway), but if the lhs is an int well...
Somehow I feel this is pretty un-rubylike, to have to have that if
statement in front of every method. Any idea if there's a more
ruby-like way to have enum-like behavior?
The idiom I usually use is:
class HockeyGear
Stick = Object.new
Helmet = Object.new
...etc...
end
Of course other than the aesthtics of looking like an enum (HockeyGear::Stick) in the source code there's no advantage over symbols. On the other hand, if someone is passing you an enum, it probably means any one of the enums is valid, so you should be checking all of them anyway, and throw an exception in the else clause. Checking whether an object is of the right type isn't very ruby-like anyway.
The idiom I usually use is:
class HockeyGear
Stick = Object.new
Helmet = Object.new
...etc...
end
Of course other than the aesthtics of looking like an enum (HockeyGear::Stick) in the source code there's no advantage over symbols. On the other hand, if someone is passing you an enum, it probably means any one of the enums is valid, so you should be checking all of them anyway, and throw an exception in the else clause. Checking whether an object is of the right type isn't very ruby-like anyway.
Hm, I wrote the attached Enum class a while ago. What do you think?
I question this though:
symbol = symbol.to_s.sub(/^[a-z]/) { |letter| letter.upcase }.to_sym
Why not just:
symbol = symbol.to_s.capitalize.to_sym
?
···
On Mar 9, 2006, at 9:33 AM, Florian Groß wrote:
Logan Capaldo wrote:
The idiom I usually use is:
class HockeyGear
Stick = Object.new
Helmet = Object.new
...etc...
end
Of course other than the aesthtics of looking like an enum (HockeyGear::Stick) in the source code there's no advantage over symbols. On the other hand, if someone is passing you an enum, it probably means any one of the enums is valid, so you should be checking all of them anyway, and throw an exception in the else clause. Checking whether an object is of the right type isn't very ruby-like anyway.
Hm, I wrote the attached Enum class a while ago. What do you think?
I've already spurled it,