#8648: Generic __call__ function for parents prevents empty input in constructor
--------------------------+-------------------------------------------------
Reporter: aschilling | Owner: robertwb
Type: defect | Status: new
Priority: major | Milestone:
Component: coercion | Keywords: element constructor
Author: | Upstream: N/A
Reviewer: | Merged:
Work_issues: |
--------------------------+-------------------------------------------------
Generic __call__ function for parents has a default value for its first
argument. This prevents from making a difference between A() and A(0).
This causes problems for crystal code, where the typical input is
A(2,1,4,3,0,...). For example:
{{{
sage: T = CrystalOfTableaux(['B',3], shape=[3])
sage: t=T(1,2,0)
sage: t
[[1, 2, 0]]
sage: T = CrystalOfTableaux(['B',3], shape=[])
sage: t=T()
sage: t # goes boom
sage: t._list # this list should be empty
[0]
}}}
Suggestion: self.__call__() could instead call right away
self._element_constructor_().
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/8648>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en.
