[WIP] @ResourceBacked property wrapper #307
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A common idiom in Siesta projects is to have UI code point at some resource that can change, and whenever it changes, to:
The Siesta docs and the example project recommend doing this via
didSet
:Swift 5.2’s property wrappers give us a better option. This PR adds a
@ResourceBacked
property wrapper that lets any variable take its value from a Siesta resource.The example above becomes:
The
doodads
variable now behaves as if it is a read-onlyDoodad
array; for example, we can do this:However, that array comes from a Siesta resource — and we can switch which resource on the fly:
Changing the resource in this way automatically:
loadIfNeeded()
.Future work on this feature
$doodads.error
. This would give better error reporting to the user if the server returns well-formed but unexpected content. (If you ask for$doodads.resource?.latestError
, you still get only underlying resource errors, since resources (at least in Siesta 1.0) have freely typed content.)loadIfNeeded