2014-09-17 3:11 GMT+02:00 Flávio Etrusco flavio.etru...@gmail.com:
On Tue, Sep 16, 2014 at 8:09 PM, Philippe phili...@quarta.com.br wrote:
on compiler implementation:
I read in this list that the group lost months due a with problem.
People use with, and I guess lot of people use it!
On Wed, Sep 17, 2014 at 4:38 AM, Frederic Da Vitoria
davito...@gmail.com wrote:
2014-09-17 3:11 GMT+02:00 Flávio Etrusco flavio.etru...@gmail.com:
On Tue, Sep 16, 2014 at 8:09 PM, Philippe phili...@quarta.com.br wrote:
on compiler implementation:
I read in this list that the group lost
2014-09-14 16:23 GMT+02:00 Mark Morgan Lloyd
markmll.fpc-pas...@telemetry.co.uk:
I'd be far happier if there were provision for declaring a temporary
shortcut symbol:
with shortcut: TSomething= TreeRoot.SubDirs[Low(TreeRoot.SubDirs)]^ do
begin
shortcut.DirLogged := true;
could the compiler avoid with pitfalls?
now the compiler attach
a property to the closest with where it finds it.
the compiler could
check if the property appears in another with of the with stack and
produce a message (hint, warning or error, which may be configurated).
is not it a way
2014-09-16 12:26 GMT+02:00 Philippe phili...@quarta.com.br:
Em 16.09.2014 05:44, Frederic Da Vitoria escreveu:
2014-09-14 16:23 GMT+02:00 Mark Morgan Lloyd
markmll.fpc-pas...@telemetry.co.uk:
I'd be far happier if there were provision for declaring a temporary
shortcut symbol:
with
On Tue, 16 Sep 2014 07:26:24 -0300
Philippe phili...@quarta.com.br wrote:
could the compiler avoid with pitfalls?
now the compiler attach
a property to the closest with where it finds it.
the compiler could
check if the property appears in another with of the with stack and
2014-09-16 12:36 GMT+02:00 Frederic Da Vitoria davito...@gmail.com:
2014-09-16 12:26 GMT+02:00 Philippe phili...@quarta.com.br:
Em 16.09.2014 05:44, Frederic Da Vitoria escreveu:
2014-09-14 16:23 GMT+02:00 Mark Morgan Lloyd
markmll.fpc-pas...@telemetry.co.uk:
I'd be far happier if
Il 16/09/2014 12:26, Philippe ha scritto:
could the compiler avoid with pitfalls?
The with construct can be very handy, but should be used with caution,
like a lot of other constructs, declarations, etc. E.g. for symbols
present with the same name in different units, depending on the
Am 16.09.2014 12:37 schrieb Mattias Gaertner nc-gaert...@netcologne.de:
On Tue, 16 Sep 2014 07:26:24 -0300
Philippe phili...@quarta.com.br wrote:
could the compiler avoid with pitfalls?
now the compiler attach
a property to the closest with where it finds it.
the compiler could
2014-09-16 14:42 GMT+02:00 Sven Barth pascaldra...@googlemail.com:
Am 16.09.2014 12:37 schrieb Mattias Gaertner nc-gaert...@netcologne.de
:
On Tue, 16 Sep 2014 07:26:24 -0300
Philippe phili...@quarta.com.br wrote:
could the compiler avoid with pitfalls?
now the compiler
I imagine that who really want to get rid from the hint ... don´t
use Pascal anyway! or do have strong test tools!!!
one point is that
(many?) people use with ... and compiler can make it safer. may be as
described Frederic Da Vitoria ... producing error when may be confused.
(but let
On 09/16/2014 03:41 PM, Philippe wrote:
I imagine that who really want to get rid from the hint ... don´t use
Pascal anyway! or do have strong test tools!!!
one point is that (many?) people use with ... and compiler can make
it safer. may be as described Frederic Da Vitoria ... producing
On Mon, Sep 15, 2014 at 2:55 AM, Sven Barth pascaldra...@googlemail.com wrote:
On 14.09.2014 18:05, Philippe wrote:
Take this example:
=== code begin ===
(...)
procedure TestWith;
var
p: PTest;
begin
New(p);
with p^ do begin
Prop1 := 42;
Prop2 := 21;
end;
on compiler implementation:
I read in this list that the group
lost months due a with problem.
People use with, and I guess lot
of people use it!
I checked the reference
http://www.freepascal.org/docs-html/ref/refsu58.html#x155-16500013.2.8
and there is not any warning ... just:
The
On Tue, Sep 16, 2014 at 8:09 PM, Philippe phili...@quarta.com.br wrote:
on compiler implementation:
I read in this list that the group lost months due a with problem.
People use with, and I guess lot of people use it!
I checked the reference
On Monday 15 September 2014 07:55:20 Sven Barth wrote:
As you can see the expression p^ is only evaluated once in the TestWith
case while it's evaluated twice in the TestWithout one. So it's only
minimally faster in this example (one less memory access), but if you
use enough members of TTest
On Mon, September 15, 2014 07:55, Sven Barth wrote:
On 14.09.2014 18:05, Philippe wrote:
someone wrote about a better performance using with. is that true?
even with a simple pointer as in:
.
.
This is the relevant code generated for TestWith:
=== asm begin ===
# [28] with p^ do begin
On 2014-09-14 11:49, Sven Barth wrote:
Though to be honest Lazarus handles with-statements in context of debugging
much more gracefully than Delphi...
We all know Lazarus is way better that Delphi - so that's always good to
know. :)
As already mentioned, human refactoring of WITH statements
On 2014-09-14 15:41, Vojtěch Čihák wrote:
because Editor is also public property of TStringGrid. Here would be
solution to rename parameter to AEditor.
Yes, that is a classic issue I have often come across.
Regards,
- Graeme -
--
fpGUI Toolkit - a cross-platform GUI toolkit using Free
On 2014-09-14 13:30, Marco van de Voort wrote:
WITH doesn't, and you risk that if your class or one of its ancestor has
such property, and your error goes unnoticed.
+1
Not to mention that you can't use tooltip debugging when it comes to the
WITH statement - at least this was the case last
Graeme Geldenhuys wrote:
As already mentioned, human refactoring of WITH statements can, and has,
caused lots of debugging issues afterwards.
If Dijkstra had written a letter to the CACM cautioning against the With
statement, I wonder whether Wirth would have headlined it With
Statement
Bernd Oppolzer wrote:
PL/1 was designed in the mid 60s, and Wirth of course knew about PL/1,
because he was at IBM at the time, and of course he was aware of the
problems and pitfalls of PL/1.
I didn't know that Wirth had been directly associated with IBM. I did
know that while at Stanford
Am 15.09.2014 09:08 schrieb Graeme Geldenhuys
mailingli...@geldenhuys.co.uk:
On 2014-09-14 13:30, Marco van de Voort wrote:
WITH doesn't, and you risk that if your class or one of its ancestor has
such property, and your error goes unnoticed.
+1
Not to mention that you can't use tooltip
On Sun, Sep 14, 2014 at 02:30:01PM +0200, Marco van de Voort wrote:
In our previous episode, J?rgen Hestermann said:
-
d:=TreeRoot.SubDirs[Low(TreeRoot.SubDirs)]; // local var d
d^.DirLogged := true;
d^.DirHatFocus
On 13 September 2014 20:29, vfclists . vfcli...@gmail.com wrote:
On 13 September 2014 20:02, Sven Barth pascaldra...@googlemail.com
wrote:
On 13.09.2014 20:13, vfclists . wrote:
According to the docs the with statement when used with mulltiple
objects only works with the last parameter.
On 2014-09-13 21:04, Mattias Gaertner wrote:
What is the rationale for such a statement, ie using multliple elements?
Less typing.
...and increases grey hair growth (due to lots more trouble debugging). :-)
Regards,
- Graeme -
--
fpGUI Toolkit - a cross-platform GUI toolkit using Free
On 2014-09-13 21:31, Marius wrote:
programmers know that and try to avoid the with statement.
+1
Regards,
- Graeme -
___
fpc-pascal maillist - fpc-pascal@lists.freepascal.org
http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Am 2014-09-13 22:31, schrieb Marius:
Mattias Gaertner wrote:
All seasoned programmers know that and try to avoid the with statement.
Realy? I love it. Consider these two varianst of code from one of my programs:
-
with
On Sun, 14 Sep 2014 11:58:22 +0200
Jürgen Hestermann juergen.hesterm...@gmx.de wrote:
Am 2014-09-13 22:31, schrieb Marius:
Mattias Gaertner wrote:
All seasoned programmers know that and try to avoid the with statement.
The quote is from Marius, not from me.
Realy? I love it. Consider
Am 2014-09-14 12:08, schrieb Mattias Gaertner:
All seasoned programmers know that and try to avoid the with statement.
The quote is from Marius, not from me.
Correct. I deleted the wrong reference. ;-(
Realy? I love it. Consider these two varianst of code from one of my
programs:
Am 14.09.2014 09:36 schrieb Graeme Geldenhuys
mailingli...@geldenhuys.co.uk:
On 2014-09-13 21:04, Mattias Gaertner wrote:
What is the rationale for such a statement, ie using multliple
elements?
Less typing.
...and increases grey hair growth (due to lots more trouble debugging).
:-)
Jürgen Hestermann wrote:
Realy? I love it. Consider these two varianst of code from one of my
programs:
This is a simpler example than the one with with the 4 levels deep
(which can be quite a puzzle if there are multiple records containing
the same fieldname(s)). And yes you may love them but
Jürgen Hestermann wrote:
Do you also prepent all function and variable names
with the unit name they come from?
Do you realy always write
LazUTF8.UTF8Delete
instead of
UTF8Delete
?
Nested WITH statements and the unit concept share the
same problem but still the benefits outweigh the drawbacks
In our previous episode, J?rgen Hestermann said:
-
d:=TreeRoot.SubDirs[Low(TreeRoot.SubDirs)]; // local var d
d^.DirLogged := true;
d^.DirHatFocus := false;
d^.SubDirsExpanded := true;
[...]
-1. !!!
I like with ... even it may give trouble times to
times!!! ... but I work alone on my programs ...
as always ... nothing
perfect! always should consider the conditions!!
Em 14.09.2014
09:30, Michael Thompson escreveu:
We have spend weeks (if not
months) off hunting
Hello All,
My two cents. The with statement is crystal clear for me. If newbies prefer to use different manners to
code the things, that are free to do it. Using some kind of intermediate variable ? That's make to code
difficult to understand, need do open begin/end blocks in some situations.
Ched wrote:
Hello All,
My two cents. The with statement is crystal clear for me. If newbies
prefer to use different manners to code the things, that are free to do
it. Using some kind of intermediate variable ? That's make to code
difficult to understand, need do open begin/end blocks in
In our previous episode, Ched said:
So, they with statement has at least one aficionados: me. Was the with
statement present if the first
versions designed by Wirth himself ?
Yes, but the problems are mostly because of the scoping complexity that OO
extensions like classes add. Specially
Am 14.09.2014 15:39, schrieb Ched:
Hello All,
My two cents. The with statement is crystal clear for me. If newbies
prefer to use different manners to code the things, that are free to
do it. Using some kind of intermediate variable ? That's make to code
difficult to understand, need do open
Hi,
once I came to troubles with with:
procedure TForm1.StringGrid1SelectEditor(Sender: TObject; aCol, aRow: Integer;
var Editor: TWinControl);
begin
with StringGrid1 do
begin
...
Editor:= ...;
...
end;
end;
because Editor is also public property of TStringGrid.
The reason why I made these comparisons to PL/1:
PL/1 was designed in the mid 60s, and Wirth of course knew about PL/1,
because he was at IBM at the time, and of course he was aware of the
problems
and pitfalls of PL/1. By including the WITH statement into PASCAL, he
probably
wanted to give
On Sunday 14 September 2014 16:34:06 Marco van de Voort wrote:
In the past I had the same opinion about with (WITHs evilness is
exaggerated) as many others, but once I bumped my head a few times while
using OO frameworks that were either not of my design or very large, I
basically stopped
In our previous episode, Martin Schreiber said:
basically stopped using it.
Why does Free Pascal not invent a safe with similar as the with of
MSElang?
The primary question is of course if there is a need for a new construct at
all. I don't know MSELang, but many new languages try to add
main problem seems to be using property whose name is common within
2 objects of the same with (or code within several with)
could it
be controlled by a compiler option?
in that case compiler may return a
hint or warning or even an error depending of the choosen configuration
...
does
El 14/09/14 17:20, Marco van de Voort ha escrit:
In our previous episode, Martin Schreiber said:
basically stopped using it.
Why does Free Pascal not invent a safe with similar as the with of
MSElang?
The primary question is of course if there is a need for a new construct at
all. I
someone wrote about a better performance using with. is that true?
even with a simple pointer as in:
with ptr^ do
begin
prop1 := ...
prop2 := ...
end;
which should be faster then
ptr^.prop1 := ...
ptr^.prop1 := ...
others wrote it is just usefull to save writing
time ...
Em
El 14/09/14 12:22, Jürgen Hestermann ha escrit:
-
d:=TreeRoot.SubDirs[Low(TreeRoot.SubDirs)]; // local var d
d^.DirLogged := true;
d^.DirHatFocus := false;
d^.SubDirsExpanded := true;
[...]
On 9/13/2014 2:02 PM, Sven Barth wrote:
It has always worked in this manner. It's just for abbreviating typing,
not for combining properties. (and then the with-variant with multiple
elements is even more seldomly used than the single-element one...)
In the Turbo Pascal days, WITH allowed for
On 14.09.2014 18:05, Philippe wrote:
someone wrote about a better performance using with. is that true?
even with a simple pointer as in:
with ptr^ do
begin
prop1 := ...
prop2 := ...
end;
which should be faster then
ptr^.prop1 := ...
ptr^.prop1 := ...
others wrote it is just usefull to
On 15.09.2014 03:06, Jim Leonard wrote:
On 9/13/2014 2:02 PM, Sven Barth wrote:
It has always worked in this manner. It's just for abbreviating typing,
not for combining properties. (and then the with-variant with multiple
elements is even more seldomly used than the single-element one...)
In
According to the docs the with statement when used with mulltiple objects
only works with the last parameter.
The statement
With A,B,C,D do Statement;
is equivalent to
With A do
With B do
With C do
With D do Statement;
--
I thought that if all the objects have the property the
On 13.09.2014 20:13, vfclists . wrote:
According to the docs the with statement when used with mulltiple
objects only works with the last parameter.
The statement
With A,B,C,D do Statement;
is equivalent to
With A do
With B do
With C do
With D do Statement;
--
I thought that if
On 13 September 2014 20:02, Sven Barth pascaldra...@googlemail.com wrote:
On 13.09.2014 20:13, vfclists . wrote:
According to the docs the with statement when used with mulltiple
objects only works with the last parameter.
The statement
With A,B,C,D do Statement;
is equivalent to
On 13.09.2014 21:29, vfclists . wrote:
What then is the nesting for if the command will only apply to the last
item with the property? Is each nested element supposed to be a property
of the enclosing element?
What is the rationale for such a statement, ie using multliple elements?
Consider
Mattias Gaertner wrote:
Less typing.
Just some generic comments in general.
Its also much harder to understand in the long run and it can even be
dangerous as stuff migh be refactored over time. All seasoned
programmers know that and try to avoid the with statement.
El 13/09/14 20:13, vfclists . ha escrit:
I thought all the 3 labels would have the caption set, but only Label3's
caption is set. Is this a difference between Delphi's Object Pascal and
FreePascal, or has Delphi's Object Pascal always worked in the same manner?
The with syntax comes from
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