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J. Moringen, 06/12/2011 09:30 PM
mention C++ limitations for strings

Types

Wire Schema <-> Programming Language Types Mapping

This section documents the mapping between wire schemas, designators of which are included in RSB's notifications, and corresponding programming language types. The values that are actually contained in notifications are called "String Designators" of wire schemas here.

Fundamental Types

For "fundamental" types, the mapping is based on the type mapping used by Google's protocol buffers.

Wire Schema String Designator C++ Python Java Common Lisp
Double precision float "double" double double double-float
Single precision float "float" float float float single-float
32 bit signed integer "int32" int32 int (signed-byte 32)
64 bit signed integer "int64" int64 long (signed-byte 64)
32 bit unsigned integer "uint32" uint32 int (unsigned-byte 32)
64 bit unsigned integer "uint64" uint64 long (unsigned-byte 64)
bool "bool" bool bool boolean boolean
ASCII string "ascii-string" string str String string
UTF-8 string "utf-8-string" string unicode String string
Sequence of Bytes "bytes" string ByteString (simple-array (unsigned-byte 8) (*))
Note: In C++, support for the ASCII string and UTF-8 string schemas is limited in the following ways:
  • When decoding data in either schema, invalid strings will be accepted without signaling an error
  • In both schemas, string values are represented as std::string objects which known nothing about the respective encodings
    • In particular, UTF-8 multi-byte sequences appear as multiple char s

Structured Data

  • GBP for notification serialization (not exposed to user)
  • A single serialization mechanism is applied for every transport in a single system
  • No composite support at this level
  • TODO Extend converter selection with wildcard mechnism to ease introspection and implementation of generic converters