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 Shape

extended list of types involved in an expression
 Syntax
 ``` Shape(E:LIST):LIST (of TYPE) Shape(E:MAT):MAT (of TYPE) Shape(E:RECORD):RECORD (of TYPE) Shape(E:OTHER):TYPE where OTHER stands for a type which is not LIST, MAT, or RECORD. ```

 Description
This function returns the extended list of types involved in the expression E as outlined below:
```Type(E) = LIST
In this case, Shape(E) is the list whose i-th component is the type
of  the i-th component of E.

Type(E) = MAT
In this case, Shape(E) is a matrix with (i,j)-th entry equal to the
type of the (i,j)-th entry of E.

Type(E) = RECORD
In this case, Shape(E) is a record whose fields are the types of the
fields of E.
```
Otherwise, Shape(E) is the type of E.

 Example
 ``` Use R ::= QQ[x]; L := [1,[1,"a"],x^2-x]; Shape(L); [INT, [INT, STRING], POLY] ------------------------------- R := Record[Name = "test", Contents = L]; Shape(R); Record[Contents = [INT, [INT, STRING], POLY], Name = STRING] ------------------------------- It.Name; STRING ------------------------------- ```
There are undocumented functions, IsSubShape and IsSubShapeOfSome, for determining if the shape of a CoCoA expression is a subshape of another. To see the code for these functions, enter
```  Describe Function("\$misc.IsSubShape");
Describe Function("\$misc.IsSubShapeOfSome");
```