Posted by jpluimers on 2020/12/16
Learned TWO things at once Mark Longair and VonC at [WayBack] git – Hard reset of a single file – Stack Overflow :
You can use the following command:
git checkout HEAD -- my-file.txt… which will update both the working copy of
my-file.txtand its state in the index with that from HEAD.
--basically means: treat every argument after this point as a file name. More details in this answer. Thanks to VonC for pointing this out.
Related:
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Posted by jpluimers on 2020/12/16
On my list of things to try: [WayBack] Spinettaro’s Blog: Delphi Flux application architecture.
It is about a Delphi implementation of the Facebook Flux application architecture.
Related:
Via: [WayBack] Delphi Flux application architecture A good application architecture Finding a good application architecture is not easy, but defining an architecture f… – Daniele Spinetti – Google+
Note that by using the [WayBack] CodeRage 2018 Replay | Embarcadero Academy, you are disallowed using any of what you learn in a commercial way.
Embarcadero evangelists told the public that for the Community Edition, similar terms would not be upheld, but then the sales department started sending out nasty emails to people registering Community Edition using their work email address.
[WayBack] https://www.embarcaderoacademy.com/p/terms:
under this license you may not:
- modify or copy the materials;
- use the materials for any commercial purpose, or for any public display (commercial or non-commercial);
- attempt to decompile or reverse engineer any software contained on the School’s web site;
- remove any copyright or other proprietary notations from the materials; or
- transfer the materials to another person or ‘mirror’ the materials on any other server.
–jeroen
Posted in Delphi, Development, JavaScript/ECMAScript, Scripting, Software Development, Systems Architecture, TypeScript | Leave a Comment »
Posted by jpluimers on 2020/12/16
Multi-threading is hard, knowing your primitives is important, but Embarcadero documentation is always far from complete, leading to [WayBack] System.SyncObjs.TLightweightSemaphore.Create: Please simply explain to me the parameters of this constructor, especially first, AInitialCount… – Jacek Laskowski – Google+
The concept of semaphores is universal (the free book [WayBack] The Little Book of Semaphores – Green Tea Press is great), but the implementation/wrapping can slightly differ, so on the [Archive.is] XE introduced TLightweightSemaphore.Create parameters:
Semaphore is used to allow ‘counted’ access. It allows access to as much owners as it has maximum count. If you wait on a semaphore (
WaitFor) and wait succeeds, the semaphore’s count is decremented. When it drops to 0, no newWaitwill succeed.When you call
Release, the semaphore’s count is incremented which allows somebody else to own the semaphore.Parameters simply set the initial state for this count and maximum value of the counter. Usually you’ll both set to the same value.
If you intend to use semaphores, read this. Great book.
The Little Book of Semaphores – Green Tea Pressgreenteapress.com
I know (theoretically) how a semaphore works. I even used this semaphore class in production code.
I want to create as many threads as there are cores in the processor (+ 1 additional, little loaded).fCoreController := TLightweightSemaphore.Create(TThread.ProcessorCount, TThread.ProcessorCount + 1);But now it turned out that customers who have CPUs with one core (yes, there are those), this code blocks the remaining threads. And I am looking for a reason, maybe I misunderstand this semaphore. What doesAInitialCountmean?ps. Delphi Seattle
AInitialCount is the number of entires a semaphore has left when created. If that is one less thanAMaxCountthat means you already gave one entry away. I just do a wild guess and say that you might do a Wait on the created semaphore shortly after creating it and in some other thread as well but since for one CPU yourAInitialCountis only 1, one of them will block – possibly you created a deadlock situation here.Semaphor.WaitFor) and I want to have as many threads as there are cores (+1 additional) then how should I createTLightweightSemaphoreobject?TThread.ProcessorCount + 1
–jeroen
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Posted by jpluimers on 2020/12/15
For my link archive:
–jeroen
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Posted by jpluimers on 2020/12/15
Basically the below thread goes like this: [WayBack] GExperts / Bugs / #92 Grep cannot handle UTF-16 and UTF-32 pas files
AAA, but not when running your tool under BBB; these files fail: xxx.txt and yyy.txtAAA and which version of our tool did you run under BBBAAA , but succeeds under BBBPart of the [WayBack] Short, Self Contained, Correct Example are indeed in it, but without more details it is hard to reproduce.
So without the reporter providing those details, nobody, especially not on open source projects, is going to fix it just on that bug report.
Via: [WayBack] It’s time for a gift to all Delphi developers, a new Release of GExperts. Happy Holidays! (But do spend some time with your family rather than testing G… – Thomas Mueller (dummzeuch) – Google+
Which highlights another conceptual problem from the same bug reporter: expecting a new version to have a regression of all open bugs against the new version.
That’s not how the world works, if it has ever worked that way. If your issue is not mentioned in any release notes, then assume nothing happened. If you want to bump it up, then provide more details.
–jeroen
Posted in Conference Topics, Conferences, Development, Event, How to report bugs, Issue/Bug tracking, Software Development | Leave a Comment »
Posted by jpluimers on 2020/12/15
Every now and then I see code, where a class descending from TComponent implements some interfaces, only interface references are used to the instances, and the expected behaviour is that the instances will free themselves when all the references went out of scope.
Bummer: TComponent by default is not reference counted.
It is when you assign VCLComObject an IVCLComObject which is hell to implement (Delphi provides two of them: TVCLAutoObject and TActiveFormControl. They sound heavey, and are).
Do not go that way. If you need some form of ownership in a class implementing an interface, then descend the class from TInterfacedObject, and add a field of TComponent that is the owner of things that need to be freed later on. In the destructor, free that field.
Something like this:
unit InterfacedObjectWithRootUnit; interface type TInterfacedObjectWithRoot = class(TInterfacedObject) strict private FRoot: TComponent; function GetRoot: TComponent; strict protected property Root: TComponent read GetRoot; public destructor Destroy; override; end; implementation destructor TInterfacedObjectWithRoot.Destroy; begin if Assigned(FRoot) then begin FRoot.Free(); FRoot := nil; end; inherited Destroy(); end; function TInterfacedObjectWithRoot.GetRoot: TComponent; begin if FRoot = nil then FRoot := TComponent.Create(nil); Result := FRoot; end; end.
–jeroen
Posted in Conference Topics, Conferences, Delphi, Development, Event, Software Development | Leave a Comment »
Posted by jpluimers on 2020/12/11
This should be on the reading list of every corporate manager: [WayBack] Why We Should Change The Rhythm Of Business | Corporate Rebels:
The problem arises when people bring their accounting background and mindset with them into business management. Decimals no longer works very well when the focus is on a future with lots of dynamics and uncertainty.
…
The solution is simple: (1) Targets must have natural deadlines; (2) Forecasting must be dynamic or rolling; (3) Resource allocation must be dynamic; and (4) Performance evaluation must take place when work is completed.
Or as Marjan Venema quoted:
“Yes, something is definitely wrong, but maybe more in the finance manager’s head than with the fisherman’s work rhythm!”
–jeroen
via: [WayBack] “Yes, something is definitely wrong, but maybe more in the finance manager’s head than with the fisherman’s work rhythm!” – Marjan Venema – Google+
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Posted by jpluimers on 2020/12/10
From [WayBack] Completely disable Windows 10 telemetry collection – twm’s blog:
So I don’t forget: According to an article in c’t magazine, disabling the “DiagTrack” service (“Connected User Experience and Telemetry”) will completely disable user tracking in Windows 10. They also say that they did not see any negative effects.
Source: [WayBack] Telefonierverbot in c’t 01/2019 page 172 (in German)
I saw at least one system where the service is not shown when you run Services.msc: it did not list DiagTrack, nor Connected User Experience and Telemetry. How awful is that!
The service can also be installed non older Windows versions: [WayBack] Just found DiagTrack running in Services – Tips and Tricks
Sometimes, it gets re-enabled. I think this happens during major Windows updates.
Run all commands from the console the below bold commands. The non-bold text was the output on my system. If instead of the cmd.exe console, you run a PowerShell console, then remove the bits PowerShell -Command " and " at the start and end of each command.
The first command does not require an Administrative (UAC Elevated) command prompt; the last one does.
However, the first command, needs the | Select-Object * bit as otherwise most of the fields will not be displayed, excluding for instance StartType.
powershell -Command "Get-Service -Name DiagTrack | Select-Object *"
Name : DiagTrack
RequiredServices : {RpcSs}
CanPauseAndContinue : False
CanShutdown : True
CanStop : True
DisplayName : Connected User Experiences and Telemetry
DependentServices : {}
MachineName : .
ServiceName : DiagTrack
ServicesDependedOn : {RpcSs}
ServiceHandle :
Status : Running
ServiceType : Win32OwnProcess
StartType : Automatic
Site :
Container :
On an Administrative command-prompt:
powershell -Command "Set-Service -Name DiagTrack -StartUpType Disabled" powershell -Command "Get-Service -Name DiagTrack | Stop-Service"
Two notes:
Posted in Batch-Files, CommandLine, Development, Power User, PowerShell, PowerShell, Scripting, Software Development, Windows | Leave a Comment »
Posted by jpluimers on 2020/12/10
On my list to play around with: 
[WayBack] Stofradar – RevSpace.
It gets data from [WayBack] luftdaten.info – Feinstaub selber messen – Open Data und Citizen Science aus Stuttgart , then visualises it.
Via: [WayBack] Helga van Leur on Twitter: “Deze animatie van de uitstoot fijnstof tijdens jaarwisseling is ook treffend… Opvallend is hotspot Veghel e.o. en op Veluwe. Bron: …”
—jeroen
Posted in Development, Software Development, Web Development | Leave a Comment »
Posted by jpluimers on 2020/12/10
I really dislike using regular expressions, mainly because every time I bump into code using them either:
For more background on when NOT to use regular expressions, remember they describe a regular grammar, and can only me implemented by a finite state machine (a state machine that can be exactly one state out of a set of finite states).
As soon as you need to parse something that needs multiple states at once, or the number of states becomes infinite,
Some background reading:
Posted in Delphi, Development, RegEx, Software Development | Leave a Comment »
The Wiert Corner - irregular stream of stuff 