Ruby... from Turing

[HyperFlexed]

I decided to learn another language...

I downloaded freeRide, but now I have no idea what to do. I've tried writing a few programs, but when I run them, the program crashes.

I have a few questions.

how do I declare a variable?
how do I initialize a variable?
how do I display something?
how would this be written in Ruby? (put "A string mixed with ", aNumVar)

Also, could someone show me the HelloWorld program in Ruby? I tried finding my own tuts, but damn. There is all this amazingly intimidating jargon all over the pages, and I don't know wtf is going on.

[Tony]

code:

text = "hello world" puts text

code:

num = 3.1415 puts "pi is #{num}"

[HyperFlexed]

wow... interesting. No formal varaible declarations.

I have another question, are programming blocks in any way like procedures and functions? It would make sense because any variable "declared" in them are not global.

thx alot btw.. I think when I get the hang of Ruby I'm going to write a big tutorial from an idiots POV.

[HyperFlexed]

P.S, anyone know any good IDE's for Ruby? I'm not really liking FreeRIDE at all. Should it just run my programs? or do I have to install some kind of Ruby thingamajigger?

[wtd]

HyperFlexed wrote:

P.S, anyone know any good IDE's for Ruby? I'm not really liking FreeRIDE at all. Should it just run my programs? or do I have to install some kind of Ruby thingamajigger?

For learning the basics, use IRB. Start -> Run, then type "irb" and hit enter.

[HyperFlexed]

wtd wrote:

HyperFlexed wrote:

P.S, anyone know any good IDE's for Ruby? I'm not really liking FreeRIDE at all. Should it just run my programs? or do I have to install some kind of Ruby thingamajigger?

For learning the basics, use IRB. Start -> Run, then type "irb" and hit enter.

ummmm... I think I need to install something first because that didn't work.

[wtd]

HyperFlexed wrote:

wow... interesting. No formal varaible declarations.

No, you don't have to declare variables. It can be a real time-saver.

HyperFlexed wrote:

I have another question, are programming blocks in any way like procedures and functions? It would make sense because any variable "declared" in them are not global.

Somewhat. There are a few ways of creating a block. We can either explicitly create a new Proc object:

code:

add = Proc.new { |a, b| a + b }

We can use the lamnda method, which often jives better with math people:

code:

add = lambda { |a, b| a + b }

And now, if we have a function which takes a block as an argument...

The & indicates the argument is a block

code:

def two_and_two(&block)    block.call(2, 4) end

We can either call it using the existing block:

code:

two_and_two(add)

Or we can pass it a new block:

code:

two_and_two { |a, b| a + b }

The other way to use a block with a function is to "yield" the variables out to any block that might be included.

code:

def two_and_two    yield 2, 2 end

And we can call it in the same way:

code:

two_and_two { |a, b| a + b }

The power of this, vs. other methods in other languages is... what if I want to multiply two and two?

code:

two_and_two { |a, b| a * b }

[wtd]

HyperFlexed wrote:

wtd wrote:

HyperFlexed wrote:

P.S, anyone know any good IDE's for Ruby? I'm not really liking FreeRIDE at all. Should it just run my programs? or do I have to install some kind of Ruby thingamajigger?

For learning the basics, use IRB. Start -> Run, then type "irb" and hit enter.

ummmm... I think I need to install something first because that didn't work.

http://rubyinstaller.rubyforge.org/wiki/wiki.pl

[HyperFlexed]

all those code examples, are all of those things keywords or something?

ruby is very minimalist. I think it's retarted.

[Tony]

I think you should take a break... *click click* We'll see you tomorrow

[wtd]

HyperFlexed wrote:

all those code examples, are all of those things keywords or something?

Only "def", "end", ".", and the basic "{ | | }" construct are part of the syntax.

"Proc" is a class, "new" is a method of that class, "two_and_two" is a user-defined method, and "lambda" is a method of the Object class.

[Andy]

HyperFlexed wrote:

ruby is very minimalist. I think it's retarted.

the point of ruby was to be simple, so its not a pain to program

[wtd]

dodge_tomahawk wrote:

HyperFlexed wrote:

ruby is very minimalist. I think it's retarted.

the point of ruby was to be simple

And don't forget flexible.