Chapter 5. Language Reference

This is the big chapter—the language reference. Here you can find every keyword, directive, function, procedure, variable, class, method, and property that is part of Delphi Pascal. Most of these items are declared in the System unit, but some are declared in SysInit. Both units are automatically included in every Delphi unit. Remember that Delphi Pascal is not case sensitive, with the sole exception of the Register procedure (to ensure compatibility with C++ Builder).

For your convenience, runtime error numbers in this chapter are followed by exception class names. The SysUtils unit maps the errors to exceptions. The exceptions are not part of the Delphi language proper, but the SysUtils unit is used in almost every Delphi project, so the exceptions are more familiar to Delphi programmers than the error numbers.

Each item falls into one of a number of categories, which are described in the following list:


A directive is an identifier that has special meaning to the compiler, but only in a specific context. Outside of that context, you are free to use directive names as ordinary identifiers. Delphi’s source editor tries to help you by showing directives in boldface when they are used in context and in plain text when used as ordinary identifiers. The editor is not always correct, though, because some of the language rules for directives are more complex than the simple editor can handle.


Not all functions are really functions; some ...

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