Book Image

Delphi High Performance

By : Primož Gabrijelčič
Book Image

Delphi High Performance

By: Primož Gabrijelčič

Overview of this book

Delphi is a cross-platform Integrated Development Environment (IDE) that supports rapid application development for Microsoft Windows, Apple Mac OS X, Google Android, iOS, and now Linux with RAD Studio 10.2. This book will be your guide to build efficient high performance applications with Delphi. The book begins by explaining how to find performance bottlenecks and apply the correct algorithm to fix them. It will teach you how to improve your algorithms before taking you through parallel programming. You’ll then explore various tools to build highly concurrent applications. After that, you’ll delve into improving the performance of your code and master cross-platform RTL improvements. Finally, we’ll go through memory management with Delphi and you’ll see how to leverage several external libraries to write better performing programs. By the end of the book, you’ll have the knowledge to create high performance applications with Delphi.
Table of Contents (16 chapters)
Title Page
Copyright and Credits
Packt Upsell

Variable capturing

Before I start writing parallel code, I have to cover something completely different. As you'll see in this chapter, the big part of the incredible usefulness of tasks and patterns is the ability to use them in combination with anonymous methods and variable capturing. As powerful as that combination is, however, it also brings in some problems.

The code in this chapter will frequently run into the problem of capturing a loop variable. Instead of trying to explain this problem at the same time as dealing with the already hard concepts of parallel code, I decided to write a simple program that demonstrates the problem and does nothing more.

The code in the AnonMethod project tries to write out the numbers from 1 to 20 in a convoluted way. For each value of i, the code calls TThread.ForceQueue and passes in an anonymous method that calls Log(i) to write the value into a ListBox.

The problem with the following code lies in the programmer's assumptions. When you write code like...