BigfootDev/flatbuffers
1
0
Fork 1
mirror of https://github.com/google/flatbuffers.git synced 2026-06-20 17:05:07 +00:00
Code Issues Packages Projects Releases Wiki Activity

Internal doc (#4409)

Browse Source 
* Add information about flexbuffer bool and null encoding

* Fix spelling errors

* Fix encoding example for flexbuffer map
This commit is contained in:
rouzier
2017-08-14 11:33:38 -04:00
committed by Wouter van Oortmerssen
parent d5f5d382eb
commit b4e91091ec
1 changed files with 10 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

16
docs/source/Internals.md
View File

@@ -374,6 +374,10 @@ The offset version is useful to encode costly 64bit (or even 32bit) quantities
into vectors / maps of smaller sizes, and to share / repeat a value multiple into vectors / maps of smaller sizes, and to share / repeat a value multiple
times. times.
### Booleans and Nulls
Booleans (`TYPE_BOOL`) and nulls (`TYPE_NULL`) are encoded as inlined unsigned integers.
### Blobs, Strings and Keys. ### Blobs, Strings and Keys.
A blob (`TYPE_BLOB`) is encoded similar to a vector, with one difference: the A blob (`TYPE_BLOB`) is encoded similar to a vector, with one difference: the
@@ -414,19 +418,19 @@ that lookups can be made using binary search.
The reason the key vector is a seperate structure from the value vector is The reason the key vector is a seperate structure from the value vector is
such that it can be shared between multiple value vectors, and also to such that it can be shared between multiple value vectors, and also to
allow it to be treated as its own indivual vector in code. allow it to be treated as its own individual vector in code.
An example map { foo: 13, bar: 14 } would be encoded as: An example map { foo: 13, bar: 14 } would be encoded as:
0 : uint8_t 'f', 'o', 'o', 0 0 : uint8_t 'b', 'a', 'r', 0
4 : uint8_t 'b', 'a', 'r', 0 4 : uint8_t 'f', 'o', 'o', 0
8 : uint8_t 2 // key vector of size 2 8 : uint8_t 2 // key vector of size 2
// key vector offset points here // key vector offset points here
9 : uint8_t 9, 6 // offsets to foo_key and bar_key 9 : uint8_t 9, 6 // offsets to bar_key and foo_key
11: uint8_t 3, 1 // offset to key vector, and its byte width 11: uint8_t 2, 1 // offset to key vector, and its byte width
13: uint8_t 2 // value vector of size 13: uint8_t 2 // value vector of size
// value vector offset points here // value vector offset points here
14: uint8_t 13, 14 // values 14: uint8_t 14, 13 // values
16: uint8_t 4, 4 // types 16: uint8_t 4, 4 // types
### The root ### The root