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2.6.1 Introduction to RECORD
A record is a data type in CoCoA representing a list of bindings of the form name to object.

Example 
/**/  Use R ::= QQ[x,y,z];
/**/  P := record[ I := ideal(x,y^2-z), F := x^2 + y, Misc := [1,3,4]];
/**/  P.I;
ideal(x, y^2 -z)
/**/ P["I"];
ideal(x, y^2 -z)

/**/  P.Misc;
[1, 3, 4]
/**/  P.Misc[2];
3

/**/  P.Date := "1/1/98";
/**/ indent(P);
record[
  Date := "1/1/98",
  F := x^2 +y,
  I := ideal(x, y^2 -z),
  Misc := [1, 3, 4]
]

/**/  P["Misc",3];  -- equivalent to P.Misc[3]
4
Each entry in a record is called a field. Note that records are open in the sense that their fields can be extended, as shown in the previous example. At present, there is no function for deleting fields from a record, one must rewrite the record, selecting the fields to retain:

Example 
/**/   P := record[A := 2, B := 3, C := 5, D := 7];
/**/   Q := record[];

  Foreach F In Fields(P) Do
    If F <> "C" Then Q[F] := P[F]; EndIf;
  EndForeach;

/**/  P := Q;
/**/  P;
record[A := 2, B := 3, D := 7]