Extended Pascal is the name given to the version of Pascal specified in International Organization for Standardization (ISO) standard 10206. It specifies an enhanced version of the Standard Pascal language that was specified in the ISO 7185 specification. The 214-page ISO 10206 document was published in May 1991 and not been revised since.
Enhancements to Standard Pascal
- Modularity and separate compilation (implemented with new keywords module, import, export, only, qualified and protected).
- Direct access file handing (via SeekRead, SeekWrite, SeekUpdate and update procedures, and the position, LastPosition and empty functions as well as an update file mode).
- The procedure extend prepares an existing file for appending data
- The declaration parts of a program (labels, constants, types, variables, procedures, and functions) can appear in any order
- Complex numbers
In addition to all the reserved words of Standard Pascal the following (referred to as word-symbols in the ISO 10206 document) have been added to Extended Pascal:
- and_then (short circuit version of "and"; right side not evaluated if not necessary)
- or_else (short circuit version of "or"; right side not evaluated if not necessary)
- otherwise (used with the case statement and variant records)
- pow (exponentiation for integer, real and complex numbers to real and integer powers)
In addition to all the symbols of Standard Pascal the following have been added to Extended Pascal:
- ** (exponentiation for integer, real and complex numbers to real and integer powers)
- >< (computes a set symmetric difference)
- ISO/IEC 10206:1991: Extended Pascal standard