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I have no issue with Microsoft wanting to patch the OS and bundled applications to make them more reliable.  The problem I have is that Windows 10 Updates are always being applied at an inconvenient time.  If you defer an update you have limited choices, and more often than not, Windows just re-starts on it’s own to apply them without me even knowing one was pending.  I have a bad habit of keeping scratch notes in a NotePad++ file and not saving it.  More than once Windows has re-started and I’ve lost those notes.

The worst thing is, it can take Windows a long time to apply an update and in the mean time you’re twiddling your thumbs.  What was wrong with the way updates have been handled for the last ~20 years?  Worse yet, some of those Windows Updates have caused issues, and required rollbacks.

We all know software is more complex than ever and hard to get right, so why would Microsoft force updates upon their user base?  At least let the user have the illusion they are in control of their own computer.  Apple notifies of updates for Mac OS/X, but they don’t apply them automatically.

Nothing alienates a user more than being inconvenienced by their OS, and there are lots of free alternatives these days.

I just created a VM for the Beta test and decided I am going to use it on my Mac for a change. Rather than using a KVM I bought a Logitech M510 mouse, and K750 PC keyboard and bound it to one unifying receiver. Normally I just pull the USB receiver from my PC, put it into my Mac mini, switch the input on my display and I’m off to the races. This is not ideal in that some Mac keyboard mappings are then unavailable to me, but since I mainly run Windows VMs, that was okay until a leg broke on my PC keyboard.

I decided that I would start using my Mac K750, but re-discovered that the function keys are by default mapped to Mac OS/X special functions, and to use the function keys I had to press the fn + F which is a pain because of the location of the fn key and my muscle memory.

I tried using the tips on Malcolm Groves blog but without success as I am running High Sierra. I even installed Karabiner to remap the function keys to normal F keys and that didn’t seem to work for me. What did work was installing the Logitech Control Center. I didn’t have to re-map any keys it just worked…

I of course have VMWare Fusion 10’s Windows 10 Profile Keyboard mapping set to disable Mac OS Host keyboard shortcuts.

Now the only issue I have is that the Logitech M510 mouse does not track very well, and sometimes appears to lose it’s connection to the receiver.  If I lift it up and put it back down, I get my mouse cursor back, but it’s so frustrating I have started using an old Bluetooth Apple Mouse I bought at a garage sale for 25 cents.  Apparently Logitech is known for poor Mac support.

I started using Object Pascal (Delphi) because it was VB like without the ugly syntax of VB, and it had the power of C++.   Namely that you could create as well as consume COM objects and it was natively compiled with at the time a very fast compiler when compared to C++.  The VCL was a stable UI framework that was simple to use and flexible enough that unusual use cases were still possible.

Sadly, now I use Delphi less and less and for maintenance work only, or personal and open source projects.  The community has dwindled from what it was once, local jobs are harder to find, and many luminaries have been lost to the evil empire (M$) and it’s technology.

I must admit that I am now working predominantly on C# .NET Core projects. I would gladly come back from the dark side if someone wanted to entice me with a interesting Delphi project. I find C# syntax more terse and unreadable than Object Pascal, but there is no mistaking the power of LINQ, the PPL, and the abundance of open source projects and technical resources. .NET native also makes adoption of C# even more tempting. If they can write Kestrel in C# you should be able to write anything that requires good performance in C#. I would love to see some Delphi web server benchmarks and how they compare to Kestrel. Favorable results might generate more interest in Delphi as would compiler benchmarks.

I love Delphi. I wish it a bright future.  Without new developers it will most certainly fade away over time.  New developers shy away from languages that won’t get them jobs.  An investment in learning a language, an IDE, and run-time libraries simply has to pay off.  Without a growing market share, expensive tools have to provide developers with a competitive edge. For this reason, I applaud EMBT’s release of the Community Edition. I hope it will bring new blood into the development community and spark more open source projects. There are some amazing open source projects out there that could use Community Edition to further their efforts.

There are also many exciting things happening in the land of Pascal that I hope will expand the community. REMObjects has released their Oxygene compiler that can also target WASM as well as native code. Smart Mobile Studio has released version 3 of their Pascal language targeting Javascript, and TMS has introduced a similar product called WebCore based on the FPC Javascript transpiler.  EMBT has hired Jon Aasenden and purchased Sencha so who knows what they have planned. With UniGUI and other frameworks Object Pascal (or rather different dialects) have many more options to target the web than only a couple years ago. I long for the day when I could use the same Object Pascal language for web, desktop, mobile and server development without compromising the results. Is it time for a language standard?

I just bought a pair of BlueDio T4S headphones from Amazon.  I received the package and went to the Bluedio site to verify my purchase for warranty purposes, only to discover that BlueDio is offering the same headphones to consumers for $56.99 ($3 less than Amazon).

I called Amazon to find out why this was the case, and discovered they do not offer a lowest price guarantee like a lot of brick and mortar stores, and claimed they have no control over manufacturers offering their products directly to consumers.

I find it hard to believe that Amazon does not have anti-competition agreements with their vendors, otherwise why would anyone go to Amazon other than to find the product they wished to purchase and then buy it directly from the manufacturer?  The whole capitalistic distribution model would no longer apply, and Amazon as a middleman could be completely cut out.

The moral of the story is, caveat emptor (buyer beware), you may not get the best price from Amazon, so do some research before buying there.

Quite often new features are added into a code stream for demonstration purposes, or need to be hidden because they are not quite ready for release (especially true for monolithic EXEs), or the client cannot upgrade their database structures yet.

There usually are various home grown approaches to accomplish this ranging from command line parameters (beta switches to enable or disable functionality), to one off database metadata queries.  These approaches can be unified in an interface added to your database “data session” as shown in the following code snippets.

type
  TFeatureSupportedPredicate = reference to function(DataSession :IDataSession): Boolean;
  TFeatureInfo = class(TObject)
    Supported :integer;
    FeatureSupportedPredicate :TFeatureSupportedPredicate;
  public
    constructor Create;
  end;

  constructor TFeatureInfo.Create;
  begin
    inherited;
    Supported := -1;  //used to indicate the test for existence has not been performed
  end

type
  TDataSession  = class(TInterfacedObject,IDataSession)
  var
    FFeatureSupportDictionary :TDictionary<string,TFeatureInfo>;
    constructor Create; override;
  end;


  constructor  TDataSession.Create;
  begin
    //do some stuff
    FFeatureSupportDictionary := TDictionary<string,TFeatureInfo>.Create;
  end;

procedure TDataSession.AddFeatureSupportPredicate(
            const FeatureName :string;
            Predicate :TFeatureSupportedPredicate);
var
  FeatureInfo :TFeatureInfo;
begin
  if FFeatureSupportDictionary.ContainsKey(FeatureName) then
    raise EFeatureSupportException.
                      CreateFmt('A Feature Support Predicate is already '+
                                'registered with the Name: ''%s'' ',[FeatureName]);
  FeatureInfo := TFeatureInfo.Create;
  FeatureInfo.FeatureSupportedPredicate := Predicate;
  FFeatureSupportDictionary.Add(FeatureName,FeatureInfo);
end;

function TDataSession.IsFeatureSupported(const FeatureName :string) :boolean;
var
  FeatureInfo :TFeatureInfo;
begin
  Result := False;
  if FFeatureSupportDictionary.TryGetValue(FeatureName,FeatureInfo) then
  begin
    if FeatureInfo.Supported = -1 then
      FeatureInfo.Supported := ifthen(FeatureInfo.FeatureSupportedPredicate(Self),1,0);
    Result := Boolean(FeatureInfo.Supported);
  end;
end;

Now wherever you pass or inject your IDataSession interface, which in a Client/Server application is almost everywhere, you will have access to the FeatureSupport functionality, and you can add/test predicates with the following code snippets:

  AddFeatureSupportPredicate(SomeFeature,
    function(DataSession: IDataSession): Boolean
    begin
      Result := DataSession.TableExists('SomeTableForTheFeature');
    end);

if DataSession.IsFeatureSupported(SomeFeature) then ....

We all know that software engineering is not at all like any other engineering discipline.  It is both a creative endeavor and an expression of technical acumen.  Applying the term “engineer” to this career is somewhat akin to the title “Domestic Engineer”.  If wasn’t, software engineers would not take an initial design, and then change the design after 90% of it was implemented as a SOP (standard operation procedure).  If civil engineering did such a thing you would see a lot more bridges collapse, and buildings like this one

Plans Change

String handling in Delphi has always been quick, but this has lead to the abuse of the data type.  I have seen code where strings are used to store all kinds of data (ie: Float) and is continually converted back and forth depending on whether it’s needed for the UI, a calculation, or to generate dynamic SQL.  Whenever data is stringified, it is open to interpretation by all consumers of that data.  Should it be handled as a string or converted to another data type and if so what type with what kind of precision and scale is necessary to avoid loss?  Who is responsible for conversion (the caller or the callee)?

By not using the native type for a given piece of data it becomes unclear as to how the data should be transformed in order for it to be stored for example to disk in the form of a config file entry, or used as a string in a SQL clause built using the Format() function.  Environmentally sensitive functions like Format() can cause massive code breakage when the user changes for example the decimal separator character, resulting in invalid SQL statements being generated.

The identifier name used for fields or variables representing data from a database column may be re-used to identify the stringified fields, causing confusion and compilation errors over the data type differences if hungarian or some other notation is not used as part of variable names.

Once data is stringified, there is no longer a data contract, and what ensues is a lot of wet (aka not DRY) brittle code (repeated data conversions) thrown together in a haphazard fashion in an effort to just “make it work”.  Making little changes like supporting different locales with say a comma instead of a decimal point for float values becomes a painful experiment if the applications are not properly layered.

My advice; write true native code, keeping fields and variables in their native type, and avoid stringification as much as possible.

I installed the latest CnPack’s Wizards 1.09.89 a couple days ago and DX Seattle suddenly seemed much slower, sometimes pausing for several seconds before presenting an hour glass and coming back to life.  A few times Windows actually detected it as not responding and prompted if I wanted to Debug or Close Delphi.

Today I uninstalled CnPack and DX Seattle is again responsive.  Too bad, I like a few of their add-ins.  Hopefully a subsequent release will resolve it.

At work I have an SSD which is only 220 GB so it is almost full almost all of the time.  Gone are the days of lean software deployments, and I am a hoarder when it comes to information.  As a result, I was attempting to install DX Seattle on my SSD and Install Aware told me I had sufficient space after unselecting various features.

After proceeding, Install Aware told me it does not have enough!

In the end I did manage to free enough space to get DX Seattle installed, although it was like playing Russian roulette.  I ended up removing vital components for SQL Server Management studio that I then had to repair.

I recently upgraded to DX Seattle which contains the long awaited (7+ releases) resolution for the “Out of Memory” issue.  I was pleased to see that DX Seattle is now Large Memory Address aware, in addition to using memory more efficiently according to Marco Cantu.

So far, after installing Update 1 with the Modern Style hot fix I have not experienced a single Out of Memory error.  As a result, we are upgrading our licenses for the first time in 3 years even though there is a big push to move the core products to .NET.  If only EMBT would have addressed this earlier, perhaps we wouldn’t be so motivated to move.