9 Dispatch (original) (raw)

9 Dispatch🔗ℹ

This module provides syntax for building a role-aware dispatch function.

(dispatch-rules+roles dispatch-clause ... maybe-else-clause)
dispatch-clause = [dispatch-pattern maybe-method maybe-roles maybe-name dispatch-fun] dispatch-pattern = () | (string . dispatch-pattern)	(bidi-match-expander ... . dispatch-pattern)	(bidi-match-expander . dispatch-pattern) maybe-method =	#:method method maybe-roles =	#:roles (role ...) maybe-name =	#:name name maybe-else-clause =	[else else-fun] method = pat role = id name = symbol?
else-fun : (-> request? response?) dispatch-fun : (-> request? any/c ... response?)

Like dispatch-rules but each dispatch-clause takes an optional list of roles and an optional name.

Returns three values: the first being a dispatcher function like indispatch-rules, the second a function that can generate reverse URIs and the third a function that, given arequest, can return the required set of roles for the matching dispatch-fun.

Reverse URI generation is different from dispatch-rules in that the first argument is a symbol representing the name of the route rather than the specific dispatch-fun that was used. This helps avoid deep dependency chains between routes. The name for a route is either the value passed to maybe-name or the name of its dispatch function.