![]() Borland licensed Hejlsberg's "PolyPascal" compiler core ( Poly Data was the name of Hejlsberg's company in Denmark), and added the user interface and editor. The Turbo Pascal compiler was based on the Blue Label Pascal compiler originally produced for the NasSys cassette-based operating system of the Nascom microcomputer in 1981 by Anders Hejlsberg. The program was sold by direct mail order for US$49.95, without going through established sales channels (retailers or resellers). Kahn's idea was to package all these functions in an integrated programming toolkit designed to have much better performance and resource utilisation than the usual professional development tools, and charge a low price for a package integrating a custom text editor, compiler, and all functionality need to produce executable programs. Vendors of software development tools aimed their products at professional developers, and the price for these basic tools plus ancillary tools like profilers ran into the hundreds of dollars. ![]() This process was less resource-intensive than the later integrated development environment (IDE). For example, the Microsoft Pascal system consisted of two compiler passes and a final linking pass (which could take minutes on systems with only floppy disks for secondary storage, although programs were very much smaller than they are today). ![]() In the early IBM PC market (1981–1983) the major programming tool vendors all made compilers that worked in a similar fashion. Programmers wrote source code using a text editor the source code was then compiled into object code (often requiring multiple passes), and a linker combined object code with runtime libraries to produce an executable program. Historically, the vast majority of programmers saw their workflow in terms of the edit/compile/link cycle, with separate tools dedicated to each task. Philippe Kahn first saw an opportunity for Borland, his newly formed software company, in the field of programming tools. The name Borland Pascal is also used more generically for Borland's dialect of the Pascal programming language, significantly different from Standard Pascal.īorland has released three old versions of Turbo Pascal free of charge because of their historical interest: the original Turbo Pascal (now known as 1.0), and versions 3.02 and 5.5 for DOS. Turbo Pascal, and the later but similar Turbo C, made Borland a leader in PC-based development.įor versions 6 and 7 (last), both a lower-priced Turbo Pascal and more expensive Borland Pascal were produced Borland Pascal was more oriented toward professional software development, with more libraries and standard library source code. It was originally developed by Anders Hejlsberg at Borland, and was notable for its extremely fast compilation. Turbo Pascal is a software development system that includes a compiler and an integrated development environment (IDE) for the Pascal programming language running on CP/M, CP/M-86, and DOS. The "backing" field of a property is almost always private, since the idea of a property is to encapsulate all outside access to it.CP/M, CP/M-86, DOS, Windows 3.x, Macintosh Make it a function, not a property, if using it has a side effect or returns something random. The value of the property should not change unexpectedly. Again, the good convention is to make it behave like a constant, at least constant for this object instance with this state. The read-only properties are often used to make some field read-only from the outside. The idea is that after M圜lass.MyProperty := 123 the programmer can expect that M圜lass.MyProperty = 123. Do not convert or scale the requested value. Do not reject invalid values silently in the "setter" (raise an exception if you must). The setter function should always set the requested value, such that calling the getter yields it back. This is in fact one of the cool possibilities of a "getter" function. Note that it’s OK for getter to have some invisible side-effect, for example to cache a value of some calculation (known to produce the same results for given instance), to return it faster next time. Using COM interfaces with reference-counting disabled More stuff inside classes and nested classes ![]() Callbacks (aka events, aka pointers to functions, aka procedural variables) Containers (lists, dictionaries) using generics How the exceptions are displayed by various libraries Finally (doing things regardless if an exception occurred) Free notification observer (Castle Game Engine) Virtual methods, override and reintroduce Exposing one unit identifiers from another Enumerated and ordinal types and sets and constant-length arrays Testing single expression for multiple values (case) Logical, relational and bit-wise operators ![]()
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