2.11.3 Functional Usage
| (require web-server/formlets/lib) |
The syntactic shorthand abbreviates the construction of formlets with the following library. These combinators may be used directly to construct low-level formlets, such as those for new INPUT element types. Refer to Predefined Formlets for example low-level formlets using these combinators.
| xexpr-forest/c : contract? |
Equivalent to (listof xexpr/c)
| (formlet/c content) → contract? |
| content : any/c |
Equivalent to (-> integer? (values xexpr-forest/c (-> (listof binding?) (coerce-contract 'formlet/c content)) integer?)).
A formlet’s internal representation is a function from an initial input number to an X-expression forest rendering, a processing function, and the next allowable input number.
| (pure value) → (formlet/c any/c) |
| value : any/c |
Constructs a formlet that has no rendering and always returns value in the processing stage.
| (cross f g) → (formlet/c any/c) |
| f : (formlet/c (any/c . -> . any/c)) |
| g : (formlet/c any/c) |
Constructs a formlet with a rendering equal to the concatenation of the renderings of formlets f and g; a processing stage that applies g’s processing result to f’s processing result.
| (cross* f g ) → (formlet/c any/c) |
| f : (formlet/c (() () #:rest (listof any/c) . ->* . any/c)) |
| g : (formlet/c any/c) |
Equivalent to cross lifted to many arguments.
| (xml-forest r) → (formlet/c procedure?) |
| r : xexpr-forest/c |
Constructs a formlet with the rendering r and the identity procedure as the processing step.
| (xml r) → (formlet/c procedure?) |
| r : xexpr/c |
Equivalent to (xml-forest (list r)).
| (text r) → (formlet/c procedure?) |
| r : string? |
Equivalent to (xml r).
| (tag-xexpr tag attrs inner) → (formlet/c any/c) |
| tag : symbol? |
| attrs : (listof (list/c symbol? string?)) |
| inner : (formlet/c any/c) |
Constructs a formlet with the rendering (list (list* tag attrs inner-rendering)) where inner-rendering is the rendering of inner and the processing stage identical to inner.
| (formlet-display f) → xexpr-forest/c |
| f : (formlet/c any/c) |
Renders f.
| (formlet-process f r) → any/c |
| f : (formlet/c any/c) |
| r : request? |
Runs the processing stage of f on the bindings in r.