Overview

Reck is an open source, BSD-licensed Python package for creating lightweight, easy-to-use record types in Python 3.2+ and PyPy3.

What problem does Reck solve?

Python provides a range of data types for handling record data including dictionaries, namedtuples and SimpleNameSpaces, each with their own pros and cons.

Reck provides a factory function to easily create custom record classes that have a unique set of properties:

• mutable field values accessible using named attributes
• indexable, sliceable and iterable
• support for per-field default values (including default factory functions)
• no limit on the number of fields (named tuples are limited to 255)
• very low memory footprint

Quick taster

>>> from reck import make_rectype
>>> Point = make_rectype('Point', ['x', 'y'])  # create a new record type
>>> p = Point(1, y=2)                     # pass values by field order or fieldname
>>> p                                     # readable __repr__ with a name=value style
Point(x=1, y=2)
>>> p.x                                   # fields accessible by name
1
>>> p.x = 5                               # fields are mutable
>>> p.x
5
>>> Point3D = make_rectype('Point3D',
...     ['x', 'y', ('z', None)])          # per-field defaults can be set
>>> p = Point3D(1, 2)
>>> p
Point3D(x=1, y=2, z=None)
>>> p._update(y=3, z=4)                   # update multiple fields at a time
>>> p
Point3D(x=1, y=3, z=4)
>>> p[0] + p[1]                           # fields are indexable
4
>>> p[:2]                                 # and sliceable
[1, 3]
>>> p._asdict()                           # Convert the record to an OrderedDict
OrderedDict([('x', 1), ('y', 3), ('z', 4)])

Interested? Check out the Tutorial.