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Part of Yhc


Because Yhc is ported to several platforms with different word sizes the meaning of the various primitive integer types is non-trivial. This appears both in the descriptions in this document and also in the runtime source code.

Yhc uses both hardware dependent and hardware independent integer types.

1 Hardware Dependent

The basis of the hardware dependent type is the Word which is always the size of a native pointer (generally either 32 or 64 bits). There are then names for various subdivisions of the Word.

 Word or UInt       - unsigned integer, same size as native pointer
 HWord or HUInt     - unsigned integer, half the size of a Word
 QWord or QUInt     - unsigned integer, quarter the size of a Word
 Int                - signed integer, same size as Word
 HInt               - signed integer, same size as HWord
 QInt               - signed integer, same size as QWord

The distinction between Word and UInt (HWord and HUInt, etc) is whether the item in question is being used as a generic piece of space the same size as a pointer (Word) or whether it is used as an unsigned integer (UInt).

2 Hardware Independent

The hardware independent types are always exactly the same size on all platforms.

  UByte or UInt8    - unsigned 8 bit integer
  UInt16            - unsigned 16 bit integer
  UInt32            - unsigned 32 bit integer
  Char or Int8      - signed 8 bit integer
  Int16             - signed 16 bit integer
  Int32             - signed 32 bit integer

The different between Char and Int8 is whether it is being used as character or simply as a small integer. The difference between UByte and UInt8 is the same difference as between Word and UInt.