Hi,
Στις 20/2/2019 3:25 μ.μ., ο Henry Vermaak έγραψε:
On Wed, Feb 20, 2019 at 09:47:20AM -0300, Marcos Douglas B. Santos
wrote:
On Wed, Feb 20, 2019 at 8:32 AM Henry Vermaak
<henry.verm...@gmail.com> wrote:
I'm mostly more interested in limiting the scope to prevent
accidental use, like you. It can also offer more fine grained
control of where managed variables get freed.
Try to see restrictions as a good thing. In this case, which Pascal
doesn't allow to declare inline variables, you must split big
functions, which has many local variables, in others to have a better
understanding of the algorithm. At the end, you might have a better
design and reuse of the code. Everybody wins: you, your code, Pascal
team - as they don't need to change the compiler - and Niklaus Wirth
might not throw a curse in us.
I don't have many big functions and I've missed scoped variables in
Pascal since the early 1990s. It's been standard good practice in
software engineering for decades and all the languages I work with
support it because it's a good idea, not because it's some newfangled
fad.
But big functions happen in the real world. The fpc compiler source has
dozens of extremely long functions. Lazarus too. I think the windproc
function in the win32 interface is more than 700 lines (look at
TWindowProcHelper.DoWindowProc).
Well, people used to ( apparently still do ) write functions that were
hundreds, even thousands of lines long and they used to write them in
plain text editors (think Notepad) without the kind of support Lazarus
provided. In that environment, declaring a variable hundreds of lines
away from where it was used meant that the person reading
if (flag) limit += factor;
didn't have a lot of clues about what flag, limit and factor were.
Naming conventions like Hungarian notation were adopted to help with
this, and so were rules like declaring things close to where they are
used. Of course, these days, it's all about refactoring, and functions
are generally less than a page long, making it hard to get very much
distance between where things are declared and where they are used.
You're operating in a range of 0-20 and quibbling that maybe 7 is ok in
this particular instance, while the guy(s) who made the rule would have
LOVED to get 7 lines away and was trying to talk someone down from 700.
And on top of that, in Lazarus, you can mouse over anything and see its
type, is it a member variable, and so on. That means the need to see the
line declaring it is lessened.
( not mine but I agree 100% ).
--
Dimitrios Chr. Ioannidis
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