The following works: #lang racket/base #;1 (define ns (make-base-namespace)) #;2 (namespace-variable-value 'list #t (λ () 'not-found) ns) ; -> #<procedure:print-syntax-width> #;3 (namespace-set-variable-value! 'list 'whatever (λ () #f) ns) #;4 (namespace-undefine-variable! 'list ns) #;5 (namespace-variable-value 'list#t (λ () 'not-found) ns) ; -> not-found But when I omit line 3 it does not work: #lang racket/base #;1 (define ns (make-base-namespace)) #;2 (namespace-variable-value 'list #t (λ () 'not-found) ns) ; -> #<procedure:list> #;4 (namespace-undefine-variable! 'list ns) ;-> error namespace-undefine-variable!: given name is not defined ; name: list
This I did with: Welcome to DrRacket, version 6.2.0.5--2015-07-06(d6fa581/a) [3m]. Code in the definitions window. The problem is not typical for 'list only. The same happens with (at least some) other variables of a base-namespace. I have no clue why commenting out line 3 gives an error. Do I misinterpret the docs on namespaces? Thanks, Jos PS I use a base-namespace in a toy interpreter. It allows me to easily borrow all variables from a base-namespace. But some of them I want to undefine. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
