AS 3.0 Learning Editor/IDE?

Hi Guys,

  i'm currently a student doing a Computing Degree learning quite a broad spectrum of languages, the big heavy hitters would namely be Java/PHP, but mostly Java for the moment. I'm not great at Java beacuse i find it to big to handle and too much to understand, but i'm probably not the worst. I there do have a basic knowledge of OO cencepts. After i finish it i want to learn something new, namely AS 3.0 purely because my interests is purely in making websites and since AS 3.0 falls under the whole Web Development category, i thought why not do it in AS 3.0. Ofcourse i could have chosen to continue with Java or something new like Ruby On Rails, but i decided to choose AS 3.0 becuase it want to specialise in particular language.

I am going to purchase Learning Actionscript 3.0, http://www.amazon.co.uk/Learning-ActionScript-3-0-Beginners-Guide/dp/059652787X/ref=sr_1_1?ie=UTF8&s=books&qid=1236892387&sr=1-1
but what i would like to know is, would it be best for me to do my coding in Flash CS3/4 or a text editor?? I asked a similar question to my lecturer but it was about learning Java and his response was this
"**Well my personal opinion is that it would be better to use a text editor
rather than an IDE. I think one of the problems of IDEs for someone who
is new to programming is that they - the IDE - become the focus of
attention, rather than the program itself. Also - as you say - they
throw automated code at you, which - at best - is highly convoluted and
hard to understand.
**
Text editors keep it simple and when
you’re learning programming, you want to be able to learn ONLY the
programming
language and not the IDE as well"

So if that is the case, if i go down the editor route, what would be the best/preferred editor to use when learning the actscripting 3.0 alongside the book i will purchase?

Cheers