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create a new identifier
This function returns a string of the form
V#N where N is an
integer. Each time it is called, the integer N changes, producing a
new string. The purpose is to produce identifiers for variables or
rings. (CoCoA does not check for the unlikely event that variables of
the same form have been defined without the use of
NewId.) The
function
NewId is often used with
Var
.
The most important use for this function is for creating temporary
rings within user-defined functions. For an example, see the section
of the tutorial entitled
Rings Inside User-Defined Functions.
NewId();
V#0
-------------------------------
NewId();
V#1
-------------------------------
X := NewId();
X;
V#2
-------------------------------
Var(X) := 3;
Var(NewId()) := 4;
Describe Memory();
------------[Memory]-----------
It = V#2
V#2 = 3
V#3 = 4
X = V#2
-------------------------------
Y := NewId();
Var(Y) ::= QQ[a,b];
Use Var(Y);
RingEnvs();
["QQ", "QQt", "R", "V#6", "ZZ"]
-------------------------------
Y;
V#6
-------------------------------
Var(Y);
QQ[a,b]
-------------------------------
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