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Fixes #1103: Incorrect nested example in design/tuple.md

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Alec Grieser 2019-02-28 13:13:30 -08:00
parent af69ba035a
commit bb43d97aaa
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1 changed files with 2 additions and 2 deletions
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@ -49,7 +49,7 @@ Encoding: `b'\x05' + ''.join(map(lambda x: b'\x00\xff' if x is None else pack(x)
Test case: `pack( (“foo\x00bar”, None, ()) ) == b'\x05\x01foo\x00\xffbar\x00\x00\xff\x05\x00\x00'`
Status: Standard
The list is ended with a 0x00 byte. Nulls within the tuple are encoded as `\x00\xff`. There is no other null escaping. In particular, 0x00 bytes that are within the nested types can be left as-is as they are passed over when decoding the interior types. To show how this fixes the bug in the previous version of nested tuples, the empty tuple is now encoded as `\x05\x00` while the tuple containing only null is encoded as `\x05\x00\xff\x00`, so the first tuple will sort first.
The list ends with a 0x00 byte. Nulls within the tuple are encoded as `\x00\xff`. There is no other null escaping. In particular, 0x00 bytes that are within the nested types can be left as-is as they are passed over when decoding the interior types. To show how this fixes the bug in the previous version of nested tuples, the empty tuple is now encoded as `\x05\x00` while the tuple containing only null is encoded as `\x05\x00\xff\x00`, so the first tuple will sort first.
### **Negative arbitrary-precision Integer**
@ -90,7 +90,7 @@ Typecodes:
 `0x21` - double (64 bits)
 `0x22` - long double (80 bits)
Length: 4 - 10 bytes
Test case: `pack( -42f ) == b'=\xd7\xff\xff'`
Test case: `pack( -42f ) == b'\x20\x3d\xd7\xff\xff'`
Encoding: Big-endian IEEE binary representation, followed by the following transformation:
```python
if ord(rep[0])&0x80: # Check sign bit