1.9 Manipulating Simple HTML Documents: docs.ss

The teachpack provides three operations for creating simple “HTML” documents:

Annotation An Annotation is a symbol that starts with “<” and ends in “>”. An end annotation is one that starts with “</”.

(atom? x) → boolean?

x : any/c

Determines whether or not a Scheme value is a number, a symbol, or a string.

(annotation? x) → boolean?

x : any/c

Determines whether or not a Scheme symbol is a document annotation.

(end-annotation x) → Annotation

x : Annotation

Consumes an annotation and produces a matching ending annotation.

(write-file l) → true

l : (list-of atom)

Consumes a list of symbols and annotations and prints them out as a "file".

Sample session: set teachpack to “docs.ss”> and click RUN:

> (annotation? 0)

false

> (annotation? '<bold>)

true

> (end-annotation 0)

end-annotation: not an annotation: 0

> (write-file (list 'a 'b))

a b