Feature #11463
Add constraints to the grammar
Status:
New
Priority:
Normal
Assignee:
-
Category:
-
Target version:
-
Start date:
01/21/2016
Due date:
% Done:
0%
Estimated time:
Description
This is a proposal to add constraints to fields of protocol messages. The generated encoders and decoders would make sure the constraints are met.
Just to get a discussion going, one possible syntax would be to follow an item with :: followed by a comma-separated list of constraints. Different types would have different constraints. The optional keyword would be moved into the constraint grammar.
| Form | Affected Types | Comments |
|---|---|---|
optional |
all | Marks the field as optional |
# .. # |
int, double | Restricts the range of the integer or double. Only one range can be specified for a field. |
| string, array, binary | Restricts the size of the string/array/binary. The range can be omitted and a single number used to fix the size. |
The various integer types would go away and we would only have int (with appropriate constraints to emulate the removed types.) We could add a type keyword to define aliases and then pre-define a few, like:
type int16 = int :: -32768 .. 32767; type uint16 = int :: 0 .. 65535;
Related issues
History
#1 Updated by Richard Neswold about 5 years ago
- Related to Feature #11474: Allow fields to be individually marshalled added
#2 Updated by Richard Neswold about 5 years ago
Added a link between this issue and #11474. Both of these can be combined into a concept of "field attributes".