Add fields and interfaces matching the numeric tower.

In descending order of generality these are ``Number``, ``Complex``,
``Real``, ``Rational`` and ``Integral``. The ``Int`` class extends
``Integral``, the ``Float`` class extends ``Real``, and the
``Decimal`` class extends ``Number``.

Generalize the parsing of numbers in the Number class.

Add tests and document them.

Run the field and bootstrap field doctests as part of unittesting, not
just under tox with sphinx, and make them run on both Python 2 and 3.

Fixes #49

CHANGES.rst

@@ -87,6 +87,13 @@
   subclass, enabling a simpler constructor call. See `issue 23
   <https://github.com/zopefoundation/zope.schema/issues/23>`_.
 
+- Add fields and interfaces representing Python's numeric tower. In
+  descending order of generality these are ``Number``, ``Complex``,
+  ``Real``, ``Rational`` and ``Integral``. The ``Int`` class extends
+  ``Integral``, the ``Float`` class extends ``Real``, and the
+  ``Decimal`` class extends ``Number``. See `issue 49
+  <https://github.com/zopefoundation/zope.schema/issues/49>`_.
+
 4.5.0 (2017-07-10)
 ==================
 

docs/api.rst

@@ -41,6 +41,12 @@ Strings
 Numbers
 -------
 
+.. autoclass:: zope.schema.interfaces.INumber
+.. autoclass:: zope.schema.interfaces.IComplex
+.. autoclass:: zope.schema.interfaces.IReal
+.. autoclass:: zope.schema.interfaces.IRational
+.. autoclass:: zope.schema.interfaces.IIntegral
+
 .. autoclass:: zope.schema.interfaces.IInt
 .. autoclass:: zope.schema.interfaces.IFloat
 .. autoclass:: zope.schema.interfaces.IDecimal
@@ -141,16 +147,9 @@ Fields
 .. autoclass:: zope.schema.Field
 .. autoclass:: zope.schema.Collection
 .. autoclass:: zope.schema._field.AbstractCollection
-.. autoclass:: zope.schema.ASCII
-   :no-show-inheritance:
-.. autoclass:: zope.schema.ASCIILine
-   :no-show-inheritance:
+
 .. autoclass:: zope.schema.Bool
    :no-show-inheritance:
-.. autoclass:: zope.schema.Bytes
-   :no-show-inheritance:
-.. autoclass:: zope.schema.BytesLine
-   :no-show-inheritance:
 .. autoclass:: zope.schema.Choice
    :no-show-inheritance:
 .. autoclass:: zope.schema.Container
@@ -159,20 +158,14 @@ Fields
    :no-show-inheritance:
 .. autoclass:: zope.schema.Datetime
    :no-show-inheritance:
-.. autoclass:: zope.schema.Decimal
-   :no-show-inheritance:
 .. autoclass:: zope.schema.Dict
 .. autoclass:: zope.schema.DottedName
    :no-show-inheritance:
 
-.. autoclass:: zope.schema.Float
-   :no-show-inheritance:
 .. autoclass:: zope.schema.FrozenSet
    :no-show-inheritance:
 .. autoclass:: zope.schema.Id
    :no-show-inheritance:
-.. autoclass:: zope.schema.Int
-   :no-show-inheritance:
 .. autoclass:: zope.schema.InterfaceField
    :no-show-inheritance:
 .. autoclass:: zope.schema.Iterable
@@ -192,12 +185,6 @@ Fields
    :no-show-inheritance:
 .. autoclass:: zope.schema.Set
 .. autoclass:: zope.schema.Sequence
-.. autoclass:: zope.schema.SourceText
-   :no-show-inheritance:
-.. autoclass:: zope.schema.Text
-   :no-show-inheritance:
-.. autoclass:: zope.schema.TextLine
-   :no-show-inheritance:
 .. autoclass:: zope.schema.Time
    :no-show-inheritance:
 .. autoclass:: zope.schema.Timedelta
@@ -206,6 +193,35 @@ Fields
 .. autoclass:: zope.schema.URI
    :no-show-inheritance:
 
+Strings
+-------
+.. autoclass:: zope.schema.ASCII
+   :no-show-inheritance:
+.. autoclass:: zope.schema.ASCIILine
+   :no-show-inheritance:
+.. autoclass:: zope.schema.Bytes
+   :no-show-inheritance:
+.. autoclass:: zope.schema.BytesLine
+   :no-show-inheritance:
+.. autoclass:: zope.schema.SourceText
+   :no-show-inheritance:
+.. autoclass:: zope.schema.Text
+   :no-show-inheritance:
+.. autoclass:: zope.schema.TextLine
+   :no-show-inheritance:
+
+Numbers
+-------
+.. autoclass:: zope.schema.Number
+.. autoclass:: zope.schema.Complex
+.. autoclass:: zope.schema.Real
+.. autoclass:: zope.schema.Rational
+.. autoclass:: zope.schema.Integral
+.. autoclass:: zope.schema.Float
+.. autoclass:: zope.schema.Int
+.. autoclass:: zope.schema.Decimal
+
+
 Accessors
 =========
 

src/zope/schema/__init__.py

@@ -21,6 +21,7 @@
 from zope.schema._field import BytesLine
 from zope.schema._field import Choice
 from zope.schema._field import Collection
+from zope.schema._field import Complex
 from zope.schema._field import Container
 from zope.schema._field import Date
 from zope.schema._field import Datetime
@@ -32,20 +33,24 @@
 from zope.schema._field import FrozenSet
 from zope.schema._field import Id
 from zope.schema._field import Int
+from zope.schema._field import Integral
 from zope.schema._field import InterfaceField
 from zope.schema._field import Iterable
 from zope.schema._field import List
 from zope.schema._field import Mapping
+from zope.schema._field import MinMaxLen
 from zope.schema._field import MutableMapping
 from zope.schema._field import MutableSequence
-from zope.schema._field import MinMaxLen
 from zope.schema._field import NativeString
 from zope.schema._field import NativeStringLine
+from zope.schema._field import Number
 from zope.schema._field import Object
 from zope.schema._field import Orderable
 from zope.schema._field import Password
-from zope.schema._field import Set
+from zope.schema._field import Rational
+from zope.schema._field import Real
 from zope.schema._field import Sequence
+from zope.schema._field import Set
 from zope.schema._field import SourceText
 from zope.schema._field import Text
 from zope.schema._field import TextLine
@@ -77,6 +82,7 @@
     'BytesLine',
     'Choice',
     'Collection',
+    'Complex',
     'Container',
     'Date',
     'Datetime',
@@ -88,6 +94,7 @@
     'FrozenSet',
     'Id',
     'Int',
+    'Integral',
     'InterfaceField',
     'Iterable',
     'List',
@@ -97,9 +104,12 @@
     'MinMaxLen',
     'NativeString',
     'NativeStringLine',
+    'Number',
     'Object',
     'Orderable',
     'Password',
+    'Rational',
+    'Real',
     'Set',
     'Sequence',
     'SourceText',