Package gavo :: Package adql :: Module fieldinfo :: Class Coercions

Class Coercions

object --+
         |
        Coercions

A tree of types that can be used to infer common types.

The tree is passed in as nested sequences.

>>> c = Coercions(_CoercNode('bar', (_CoercNode('foo'), _CoercNode('baz',
...   (_CoercNode('quux'),)))))
>>> c.getSubsuming([])
'bar'
>>> c.getSubsuming(['foo'])
'foo'
>>> c.getSubsuming(['foo', 'foo'])
'foo'
>>> c.getSubsuming(['foo', 'quux'])
'bar'
>>> c.getSubsuming(['foo', 'weird'])
'bar'

Instance Methods

__init__(self, typeTree)
x.__init__(...) initializes x; see help(type(x)) for signature

source code

getSubsuming(self, typeSeq)
returns the least general type being able to represent all types within typeSeq.

source code

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __repr__, __setattr__, __sizeof__, __str__, __subclasshook__

Properties
Inherited from `object`: `__class__`

Method Details

init(self, typeTree)
(Constructor)

source code

x.__init__(...) initializes x; see help(type(x)) for signature

Overrides: object.__init__: (inherited documentation)

getSubsuming(self, typeSeq)

source code

returns the least general type being able to represent all types within typeSeq.

The method returns the root type for both an empty typeSeq or a typeSeq containing an unknown type. We don't want to fail here, and the "all-encompassing" type should handle any crap.

Class Coercions

__init__(self, typeTree) (Constructor)

getSubsuming(self, typeSeq)

init(self, typeTree)
(Constructor)