ShortString

ShortString is a fixed-length string type used in classic Pascal-based languages such as Turbo Pascal, Borland Pascal, and early Delphi. It is commonly defined as a bounded string, for example as ShortString = string[255], or as a fixed-size character array with a one-byte length prefix. The maximum logical length of a shortstring is 255 characters.

The internal representation typically uses a single length byte followed by up to 255 characters. The length byte records how many characters are actually stored, and the remaining bytes are unused. As a result, a shortstring value occupies a fixed amount of space in memory (often treated as roughly 256 bytes: 1 byte for length and up to 255 for characters). This fixed size makes shortstrings predictable in low-level contexts and when interfacing with legacy code or certain APIs.

Usage and interoperability: shortstrings support standard string operations, but their bounded nature means operations must respect the 255-character limit. They are commonly used for compatibility with older code or for interfacing with C libraries where a length-prefixed, fixed-size string is convenient. Conversions to and from dynamic string types (such as AnsiString or UnicodeString) are common, usually via explicit conversion routines or compiler-provided facilities. Pointers to shortstrings (PShortString) are used for low-level access in some runtimes.

Limitations and modern context: the 255-character limit and fixed-size storage can be restrictive, and many modern Pascal dialects prefer dynamic strings by default. ShortString remains available for compatibility and certain low-level interfaces, but developers typically use dynamic strings for new code and convert to shortstring only when interacting with legacy APIs.