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3.5.4 Objects
Every object in SINGULAR has a type and a value. In most cases it
has also a name and in some cases an attribute list. The value of an
object may be examined simply by printing it with a print command:
object; . The type of an object may be determined by means of the
typeof function, the attributes by means of the attrib
function ( typeof, attrib):
| ring r=0,x,dp;
typeof(10);
==> int
typeof(10000000000000000);
==> bigint
typeof(r);
==> ring
attrib(x);
==> no attributes
attrib(std(ideal(x)));
==> attr:isSB, type int
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Each object of type
poly ,
ideal ,
vector ,
module ,
map ,
matrix ,
number , or
resolution
belongs to a specific ring. This is also true for list , if at least one of the
objects contained in the list belongs to a ring. These objects are local
to the ring. Their names can be duplicated for other objects in other rings.
Objects from one ring can be mapped to another ring using maps or the
commands fetch or imap . See map, fetch, imap.
All other types do not belong to a ring and can be accessed within every
ring and across rings. They can be declared even if there is no active
basering.
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