From: Hayden Smith <tardis.tardis@...>
Date: 2008-05-08T20:36:54+09:00
Subject: Re: initial stages of scripting

Hi Ellie,
Thanks for the suggestions, but as is evident from this code - I believe - I 
am a relative newbie and therefore, the logic behind this - at this point - 
is beyond me. Oh well, back to the bottom of the class for me.
Cheers
----- Original Message ----- 
From: "Eleanor McHugh" <eleanor@games-with-brains.com>
To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
Sent: Thursday, May 08, 2008 9:07 PM
Subject: Re: initial stages of scripting


> On 8 May 2008, at 11:27, Hayden Smith wrote:
>> Hi there,
>> I'm a relative newbie when it comes to scripting in ruby however,  for a 
>> year 11 project at school, it is necesary for me to program a  maths 
>> utilit which requests a user - elementary school aged - to add  to 
>> numbers together to reach an answer. I've effected some coding  however, 
>> I'm a little stumpt as to why the aplet is not correctly  parsing through 
>> the loops.
>> ===script extract starts==
>> question = 1
>> unless question == 20
>> score = 0
>> number_of_questions = 0
>> num1 = rand(20)
>> num2 = rand(20)
>> correct_answer = num1 + num2
>> puts("What is #{num1} + #{num2}/?")
>> user_answer = gets.chomp!.to_i
>> unless user_answer == correct_answer
>>  puts("Sorry, that is not correct. Please try again.")
>>  user_answer = gets.chomp!.to_i
>> end
>> score += 1
>> number_of_questions += 1
>> question += 1
>> puts("Well done! That is correct.\nYou have answered #{score} out of 
>> #{number_of_questions} questions correctly.")
>> end
>> exit
>
> Hi Hayden,
>
> I hope the following answers are helpful. The idiom that you'd be  looking 
> to use in your code would be:
>
> score = 0
> 1..20.each do |question|
> # do stuff
> end
>
> where you keep track of the score yourself as part of do stuff.  Although 
> I prefer the form:
>
> 1..20.inject(0) |sum, question|
> # do stuff
> sum += some_condition ? 1 : 0
> end
>
> but that requires that the last expression in the block be the one  that 
> increments the sum variable. Extra marks if you can write the  block 
> without using any local variables ;)
>
>
> Ellie
>
> Eleanor McHugh
> Games With Brains
> http://slides.games-with-brains.net
> ----
> raise ArgumentError unless @reality.responds_to? :reason
>
>
>