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GNU Info (guile.info)Alist ExampleAlist Example ............. Here is a longer example of how alists may be used in practice. (define capitals '(("New York" . "Albany") ("Oregon" . "Salem") ("Florida" . "Miami"))) ;; What's the capital of Oregon? (assoc "Oregon" capitals) => ("Oregon" . "Salem") (assoc-ref capitals "Oregon") => "Salem" ;; We left out South Dakota. (set! capitals (assoc-set! capitals "South Dakota" "Bismarck")) capitals => (("South Dakota" . "Bismarck") ("New York" . "Albany") ("Oregon" . "Salem") ("Florida" . "Miami")) ;; And we got Florida wrong. (set! capitals (assoc-set! capitals "Florida" "Tallahassee")) capitals => (("South Dakota" . "Bismarck") ("New York" . "Albany") ("Oregon" . "Salem") ("Florida" . "Tallahassee")) ;; After Oregon secedes, we can remove it. (set! capitals (assoc-remove! capitals "Oregon")) capitals => (("South Dakota" . "Bismarck") ("New York" . "Albany") ("Florida" . "Tallahassee")) automatically generated by info2www version 1.2.2.9 |