Extracting fields from a define-type object in Scheme

Posted by Mike on Stack Overflow See other posts from Stack Overflow or by Mike
Published on 2010-04-14T00:30:35Z Indexed on 2010/04/14 0:33 UTC
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Hi,

I am trying to extract the field 'name' or 'named-expr' from the following object:

(bind 'x (num 5)) ;; note that this is not a list, but a type Binding

With the Binding definition:

(define-type Binding (bind (name symbol?) (named-expr WAE?)))

I have tried, but received the error "reference to an identifier before its definition: Binding-name." Here is what I tried typing:

(begin (Binding-name (bind 'x (num 5)))) (begin (define x (bind 'x (num 5))) (Binding-name x))

Thank you!

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