Jump to content

David Heffernan

Members
  • Content Count

    3710
  • Joined

  • Last visited

  • Days Won

    185

Everything posted by David Heffernan

  1. David Heffernan

    Updating UI using Invoke

    Works fine here. I wrote a version with the threading removed to make it simpler to understand. {$APPTYPE CONSOLE} uses System.SysUtils; function CaptureValue(Value: Integer): TProc; begin Result := procedure begin Writeln(Value); end; end; procedure Main; var i, j: Integer; Procs: TArray<TProc>; begin SetLength(Procs, 10); for i := 0 to 9 do Procs[i] := procedure begin Writeln(i); end; for j := 0 to 9 do Procs[j](); for i := 0 to 9 do Procs[i] := CaptureValue(i); for j := 0 to 9 do Procs[j](); end; begin Main; Readln; end. Output is 10 10 10 10 10 10 10 10 10 10 0 1 2 3 4 5 6 7 8 9
  2. David Heffernan

    Updating UI using Invoke

    You have captured the variable. But you need to capture the value. Capturing the value is not supported directly so you need to fake that by making a copy of the variable into a new value, one per task. More detail here http://docwiki.embarcadero.com/RADStudio/en/Anonymous_Methods_in_Delphi https://stackoverflow.com/a/24223683/505088
  3. David Heffernan

    Injecting Pascal into PHP?

    Ugh. Good luck reasoning about the security of such a thing.
  4. David Heffernan

    Add a system-menu item to all applications?

    You probably need to hook at the other processes. Not easy, and likely to be extremely brittle. Also won't work for any programs that do system menus in a non standard way.
  5. David Heffernan

    OmniThread with Database

    Would be easier for people to help if you could post a minimal repro.
  6. On each iteration, each value is modified. So, during the iteration, just keep track of the smallest value that you have seen to date.
  7. David Heffernan

    How to get the Currency Symbol in multiple platforms

    Build the ISO 4217 table into your code and lookup the currency code from the country code.
  8. David Heffernan

    Laufleistung

    No, that is the device that measures mileage
  9. David Heffernan

    Laufleistung

    No English speaker I know, here in the UK, would say anything other than mileage. This is one of those words whose meaning is now detached from its etymology.
  10. David Heffernan

    Passing back a string from an external program

    Well, there are plenty of types for which races lead to errors. But how races manifest is not part of what defines them. A race is simply unserialised access to a shared resource. There aren't multiple definitions of this term.
  11. David Heffernan

    Passing back a string from an external program

    This is the dictionary definition of a race
  12. David Heffernan

    JSON string value

    I don't buy that argument. People are using the software now. And software is never finished. There is always more to be done. So if you wait until it is done, then you never document it. My personal experience, and very strongly felt, is that writing documentation is a key part of finalising and debugging specification. So many times have I experienced this. Only when you write the documentation do you realise some of the issues that users will face. Deal with them before releasing and you don't have to spend as much time in back compat hell. My view is that writing documentation in a timely fashion actually saves time and resources in the long run.
  13. David Heffernan

    JSON string value

    Python documentation is excellent. Likewise C# documentation. And so on. Delphi is an outlier here.
  14. David Heffernan

    Passing back a string from an external program

    Reading the stdout of the child process is a very easy way to do this.
  15. David Heffernan

    DelphiTwain on 64-bit

    You followed the instructions for 64 bit compilers, made the necessary change to the code outlined on the page you linked, obtained 64 bit drivers etc?
  16. It's not clear whether you mean 64 bit Windows, or 64 bit iOS or 64 bit Linux.
  17. David Heffernan

    getProcessAffinityMask failure handling in OTL

    Silent failure as you propose does not seem very useful to me. Surely better to use RaiseLastOSError in case an API call fails.
  18. David Heffernan

    JSON string value

    Why did you decide that 2 is the answer?
  19. David Heffernan

    JSON string value

    Hmm, rather perplexing conclusion. How did you arrive at it?
  20. David Heffernan

    JSON string value

    https://stackoverflow.com/q/11785963/505088
  21. You might consider buying the book if you want it.
  22. David Heffernan

    track process execution

    No need to hook anything. And in any case, what would you hook? Every process in the entire system? The system raises WMI events when processes are created and destroyed. https://stackoverflow.com/questions/47147099/is-there-a-way-to-recieve-a-event-about-a-process-starting-in-windows
  23. David Heffernan

    A YAML Library for Delphi

    This looks mighty cool. Kudos to you once again. In my codebase at work we use an in-house bespoke wrapper of libyaml. The big difference from yours, I suspect, is that we needed to support very large files, and opted for a SAX type interface.
  24. David Heffernan

    GetMemory vs. GetMem

    But actually, that turns out to be completely wrong. At least in XE7 malloc is implemented as function malloc(size: size_t): Pointer; cdecl; begin Result := AllocMem(size); end; which is pretty lame because AllocMem is zeroising the memory. And potentially throwing an exception. So, a somewhat bogus attempt to implement malloc. Perhaps what is really going on is that GetMemory is the function that you need to call if you want to allow GetMemory(0) to return a pointer to a block of memory, ie. that GetMemory(0) <> nil. But I'm not convinced by that either since the C standard demands that malloc(0) returns a value that cannot be dereferenced, which may or may not be null. Or perhaps it is just a function that returns nil in case of error rather than raising an exception.
  25. David Heffernan

    GetMemory vs. GetMem

    I'd read that as "GetMemory exists so that the Crtl unit can implement malloc".
×