Question:confused about identical(expr) in structured type

Question:confused about identical(expr) in structured type

Maple

help on structured type says

| identical(expr) an expression identical to expr

and

The type identical(expr) matches the expression expr identically. If there is more than one expr (i.e. identical(expr1,expr2,...)), then this type matches any one of the exprN identically.

Then why does the following produce the same output?

```restart;
expr:=x*A[2]+A[1];
select(type,expr,'`*`'({anything, identical(x^2)}));
select(type,expr,'`*`'({anything, identical(x)}))
```

x*A[2]

x*A[2]

I would have expected only the second select to find x*A[2].

What do I need to only select anything*x^2 without selecting anything*x ?

Actually anything in identical gives same result

```select(type,expr,'`*`'({anything, identical(zzzzz)}));
```

x*A[2]

So I must be misunderstanding something about identical and how it works.  I want to match only anything*x^2 and nothing else. How to do that?

all these things are trivial to do use pattern matching. But in Maple, one is supposed to use structured types.

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