3.6 Mutability

Module: sage.structure.mutability

Class: Mutability

class Mutability
Mutability( self, [is_immutable=False])

Functions: is_immutable,$  $ is_mutable,$  $ set_immutable

is_immutable( self)

Return True if this object is immutable (can not be changed) and False if it is not.

To make this object immutable use self.set_immutable().

sage: v = Sequence([1,2,3,4/5])
sage: v[0] = 5
sage: v
[5, 2, 3, 4/5]
sage: v.is_immutable()
False
sage: v.set_immutable()
sage: v.is_immutable()
True

set_immutable( self)

Make this object immutable, so it can never again be changed.

sage: v = Sequence([1,2,3,4/5])
sage: v[0] = 5
sage: v
[5, 2, 3, 4/5]
sage: v.set_immutable()
sage: v[3] = 7
Traceback (most recent call last):
...
ValueError: object is immutable; please change a copy instead.

Special Functions: _require_mutable

See About this document... for information on suggesting changes.