Prior to this commit, the conversion 'T -> Option<T>' was applied in
both the path and query parts of a URI in the 'uri' macro via the
'FromUriParam' trait with no implementation for 'Option<T>' directly.
This meant that it was impossible to directly render an 'Option<T>'.
This was exactly desired for the path part, where rendering a 'None'
would yield an incorrect URI, but the restriction was too strict for the
query part, where a 'None' is entirely valid. This commit makes changes
the conversion so that it only applied to path parts and adds the
identity conversions for 'Option<T>' and 'Result<T, E>' for query parts.
The side effect is a breaking change: due to conflicting impls, the 'T'
to 'Option<T>' conversion was removed for query parts. Thus, all 'uri!'
query route arguments of type 'Option' or 'Result' must now be wrapped
in 'Some' or 'Ok'. Due to new 'Option<T> <-> Result<T, E>' conversions,
either 'Some' _and_ 'Ok' work in both contexts.
Closes#1420.
Prior to this commit, it was impossible to 'use' a route from a separate
namespace for use in a 'routes!' macro. Naturally, this was a common
source of confusion amongst users. This commit obviates this deficiency
by generating a "proxy" structure that can be imported and converted
into a 'Route'/'Catcher' or their static variants.
This change is largely backwards compatible but can break existing code
when routes are named identically to other types in the namespace.
Every code example is now fully runnable and testable. As a result, all
examples are now tested and include imports. Relevant imports are shown
by default. Code examples can be expanded to show all imports.
Fixes#432.
Sergio Benitez
Jacob Pratt
Jeb Rosen