Rev scripting preferences

Richard Gaskin ambassador at fourthworld.com
Thu Feb 8 21:27:32 EST 2007


Mark Talluto wrote:

 > On Feb 8, 2007, at 3:10 PM, Richard Gaskin wrote:
 >> The time to call a script further down the message path from
 >> the target object is such a small fraction of a microsecond
 >> that it isn't noticeable.
 >
 > You mean further *up* the message path....right Richard?  ;)

Nope.  As Jerry would say, I'm an earth worshiper. :)

In the olden days when the world was fixated on tree diagrams, many 
xTalk teachers used to draw them like trees, with the bottom being the 
start and the top being the end.  Maybe some still do.

But personally I find a tree a less fitting metaphor than pachinko, or 
any system involving things just naturally falling and sometimes 
catching on other things.

I find the top-to-bottom flow gets picked up more easily than 
bottom-to-top, for three reasons:

1. Describing the path of a message is telling a story of that message's 
journey.  Whether through diagrams or words, readers tend to look for 
the start of a story at the top of the page.

2. Everyone understands gravity.  It's a natural downward flow.  I tend 
to visualize messages as being dropped; some meet with objects on the 
way down and get handled, others fall through all the way to the ground. 
  This also helps learners understand "send":  it's not part of the 
natural flow (the "message path"), and requires effort like reversing 
the effect of gravity by throwing a ball in the air.

3. Top-to-bottom representations leverages the concept of "top-down", 
the latter being a common reference to understanding software from the 
perspective of the user experience.  Messages in Rev tend to flow in a 
way that roughly correlates with the visual representation; objects in 
front get the message first, then the card behind them, etc.  For those 
used to thinking in terms of "top-down" and "bottom-up" (nostly 
Rev-as-a-second-language learners), this fits in quite nicely.

When I first started teaching HyperTalk back in '87 I used to use the 
upside-down diagram.  But for the last decade or more I've adopted the 
one that seems simpler to grasp:

<http://www.fourthworld.com/embassy/articles/revolution_message_path.html>

-- 
  Richard Gaskin
  Fourth World Media Corporation
  ___________________________________________________________
  Ambassador at FourthWorld.com       http://www.FourthWorld.com




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