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< Eng:Scratch File Format (1.4)

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Archive.png This article or section documents a feature not included in the current version of Scratch (2.0). It is only useful from a historical perspective.
This is part of a technical description of the file format.

Inline values — nil, true, false, integers, and floats — are simply encoded inline as fields in Objects in an Object Table.

Note: References are also found as Object fields, although they are not inline values.

List of Inline Values

classID, type Squeak Function, structure
1: nil n/a (constant value)
2: true n/a (constant value)
3: false n/a (constant value)
4: SmallInteger SmallInt - signed 32-bit integer
5: SmallInteger16 SmallInt - signed 16-bit integer
6: LargePositiveInteger length: 16-bit integer, followed by that many bytes.
7: LargeNegativeInteger (same as above)
8: Float 8 bytes
"Squeak function" refers to the function in the Squeak source code used to parse that type (eg. getSmallInt, putSmallInt.)

References