Hosts are defined with the
:/ verb. It should remind you (a
little) of the characters that come before hosts in URLs.
import dispatch._ val sl = :/("www.scala-lang.org")
sl is a request to the root path of the Scala home
domain. What if we want some sub-path of it? There’s an obvious verb
val learnScala = sl / "node" / "1305"
Now we have a reference to a page (the “Learning Scala” page
sl is unchanged.
Request definitions such as these are immutable; by appending a path to one you are creating a new request object, similar to string concatenation in Java. If we don’t need to use the host for different requests, we would probably have defined this all at once:
val learnScala2 = :/("www.scala-lang.org") / "node" / "1305"
But—can’t you define this with its actual URL? Of course!
val learnScala3 = url("http://www.scala-lang.org/node/1305")
url verb is also imported from the
dispatch package and it
produces a request object like the others. It is most useful when
dealing with URLs stored externally, or discovered at runtime. For
fixed requests in your application code, building up from host and
path components is usually preferred as it lends itself to reuse.