Data Types

Agnos defines the following primitive types. Note that these types, including their aliases, are reserved names – you may not define your own type, overriding any of these names.

Value types are passed by-value, meaning, serialized to bytes and sent over the wire. This means that a copy of the original object is created on the other side.

This is unlike reference types, which are passed by-reference. For reference types, only a unique identifier is sent over the wire, while the actual object remains where it is.

Simple Types

Note

These are all value types

• bool – a boolean value: one of true or false.
• int8 – signed integer, 8 bits wide (-128..127).
• int16 – signed integer, 16 bits wide (-32768..32767).
• int32 or int – signed integer, 32 bits wide (-2^31..2^31-1).
• int64 – signed integer, 64 bits wide (-2^63..2^63-1).
• float – 64-bit floating point number (usually called double).
• datetime – a point in time, in microsecond resolution. It represents the number of microseconds from 00:00:00, January 1st, year 0 in UTC; however, its actual range is limited by the implementation:
  • In java it can only represent dates after January 1st, 1970 (limitation of java.util.Date).
  • In C++, it can only represent dates after January 1st, 1400 (limitation of boost::posix_time::ptime).
  • In python and C#, it has the full range (starting from year 0 through 9999).
• string or str – a unicode string (UTF8 encoded).
• buffer – a binary buffer (array of bytes), useful for passing binary data blobs.

By-Value Containers

Note

These are all value types

• list[V] – a list (also vector) of elements of type V. Example usage: list[int32].

• set[V] – a set (unordered collection) of unique elements of type V. Example usage: set[float].

• map[K, V] or dict[K, V] – a map of unique keys of type K to values of type V. Example usage: map[datetime, string].

• heteromap or heterodict – a heterogenous map, meaning a map contains keys of any type and values of any type.
  • In C++, the keys are limited only to the simple types (listed above); this is because STL implementation requires well-ordering on the keys. Values are unrestricted.

Containers are not limited to holding simple types only; for instance, map[int, set[str]] is a valid type.

Void

void is also a quasi-type, that can only appear as the return type of functions and methods; it is invalid in all other contexts. The name void is a reserved name as well.

By-Reference Collections

These are the by-reference counterparts of the by-value collections listed above.

Note

THESE TYPES ARE NOT IMPLEMENTED IN VERSION 1.0. They are only given here because these names are reserved for future use.

• reflist[V] – To be implemented in a future version
• refset[V] – To be implemented in a future version
• refmapp[K, V] or refdict[K, V] – To be implemented in a future version