Re: Beginner's Language?

[David Gillon <david.gillon@baesystems.com>]

Ola Rinta-Koski wrote:
> 
> (let ((foo 0))
>   (dotimes (i 5)
>     (incf foo (read)))
>   foo)
> 
> > Now look at it. Could a neophite with literally *zero*
> > experience in programming computers read it and stand a chance of
> > understanding what it does or how it does it?
> 
>   Not being a neophyte, I'll just have to guess: yes and yes.

Well, I'll admit that despite a CS degree (including a course
specifically aimed at comparing different languages) and fifteen years
in the industry I can't claim to know what this code does, so any
complete neophyte is going to be floundering. I can guess we have a loop
doing something to Foo, but beyond that ...? Sum five (could also be 6)
inputs seems most likely, but that's based on my knowledge of parallel
constructs in other languages and therefore more than a true neophyte
could get.

Despite all the criticisms that can legitimately be levelled at BASIC I
originally taught myself to code from BASIC examples in computer
magazines, I don't believe that would have been true if they had looked
like the example above instead of paralleling natural language. And what
BASIC does better than this Pascal and Ada do better still.

There's also a strong cultural element to be considered beyond the
strict grammar of the language. A language that stays close to natural
language (at least for the anglophone part of the population), which
encourages meaningful variable names and cleanly structured, readable,
well commented code is going to be far easier for someone with limited
knowledge to understand (or maintain). A CS/SE course that teaches good
coding practise rather than just coding is going to produce people
who'll be both more useful to their employers and gain the course a good
reputation

I much prefer the following to the example above and I believe that even
with all comments stripped out it would be inherently easier to
understand for a struggling student:

procedure Sum_Five_Values is

  -- Description : 
  --   Example showing clear coding practice, sums five integer inputs 
  --   and displays result

  -- Input Parameters  : 
  --   None (uses keyboard)
  -- Output Parameters : 
  --   None (uses screen)

  -- Modification History :
  --   10-05-2001, Initial version, DWG
  --   <DD-MM-YYYY>,<Description of change>,<Author>

  Total_Count   : Integer := 0;
  Entered_Value : Integer;

begin

  -- Sum five inputs from the keyboard
  for Loop_Counter := 1 .. 5 do
  begin
    Put_Line ("Enter an integer value and press return");
    Get (Entered_Value);
    Total_Count := Total_Count + Entered_Value;
  end;

  -- report the final result to the screen
  Put("Total Value = ");
  Put_Line(Total_Count);

end Sum_Five_Values;

-- 

David Gillon