On Sat, Jun 14, 2014 at 06:23:08PM +0530, diliup gabadamudalige wrote:
> Say if I have a lot of Lists, strings and variables used to carry data to
> and from various functions why can't I have a class with all these in it?
Of course you *can*, but you *should not*. Read on...
[...]
> so I declare
>
> class Containers():
> def __init__(self):
> self.last_selected_scale= ""
> self.scale_notes = ""
> self.arpeggionotes = ""
etc.
> now i initiate the class with
> v=Containers()
So now you write code where everything you use starts with "v.". What
does the v. do? How does it help your programming?
Answer: it doesn't. It just makes an extra two characters to type.
Compare the code you would write if you just defined the variables
directly:
# Option 1
last_selected_scale = ""
scale_notes = ""
arpeggionotes = ""
do_something(last_selected_scale)
do_another_thing(scale_notes, arpeggionotes)
# Versus option 2:
class Containers():
def __init__(self):
self.last_selected_scale = ""
self.scale_notes = ""
self.arpeggionotes = ""
v = Container()
do_something(v.last_selected_scale)
do_another_thing(v.scale_notes, v.arpeggionotes)
The two options do *exactly* the same thing, but Option 2 takes much
more typing and reading. For what benefit?
The only benefit is if you might have multiple Containers at the same
time:
keyboard_a = Container()
keyboard_b = Container()
do_something(keyboard_a.last_selected_scale)
do_another_thing(keyboard_b.scale_notes, keyboard_b.arpeggionotes)
Now you can play and record with two keyboards at the same time.
(Perhaps you have four arms? *smile*) In this case, the extra cost of
using a class pays for itself. Otherwise, it is just wasted effort.
--
Steven
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