Use a single template function for each of {to,from}ExpressionValue, always dispatching to ValueConverter.
Remove unused ValueConverter::ExpressionType typedefs.
When detecting an expression used as a filter, relax the check for expressions to allow comparison expressions to contain a fourth member for the collator.
Based on patch from @lbud (Lauren Budorick).
Give `HeatmapColorPropertyValue` a more generic name,
since the same value type will be used for both `heatmap-color`
and `line-gradient` properties.
* Introduce AspiringActor, EstablishedActor
This pair of objects represents the two-phase (parent-thread /
child-thread) construction that's needed to support constructing
Thread<Object> without blocking until the child thread is up and
running.
An `AspiringActor<O>` is responsible for:
- ownership of the actor's `Mailbox`
- allocating the memory for (but *not* constructing) the target object `O`
Using these two pieces--the mailbox and a stable address for `O`--an
`AspiringActor<O>` can accept messages for the target object, or provide
`ActorRef<O>`s that do so, before the object has actually been
constructed by the corresponding `EstablishedActor<O>`. (Such messages
are queued in the mailbox until after the object is constructed.)
This allows for an `AspiringActor<O>` to be created and safely used by a
thread other than the one on which the target object will (eventually)
live.
An `EstablishedActor<O>` is responsible for managing the lifetime of the
target object `O` and the open/closed state of the parent's `mailbox`.
The `O` object's lifetime is contained by that of its owning
`EstablishedActor<O>`: the `EstablishedActor` constructor executes the
`O` constructor via "placement new", constructing it at the address
provided by the parent `AspiringActor`, and the `~EstablishedActor`
destructor similarly executes the `~O` destructor (after closing the
mailbox). `EstablishedActor` should therefore live entirely on the
thread intended to own `O`.
* Remove Actor#{invoke,ask}
Legacy filters aren't part of the style specification, but you can generate them by parsing a legacy filter in a stylesheet, and obtaining the parsed Filter and serializing it.
* Tile timing
* Refactor logging code
* Keep the scope of `messageStream` constrained
* Make log message more clear
* Fix crash issue if onlineResponse.data is null
Since placements will be committed even if they do not need the full
fade duration to fade features in, we need the new `fadeStartTime` to
keep track of how long we still need to fade. This is important because
if we fade too long we will trigger another placement and never stop
rendering.
* Fix crash due to mixing legacy filters and expressions
In some cases, (invalid) nested filters that used a mix of legacy filter
syntax and expression syntax caused a crash due to a failure to
propagate parsing errors from deeper within the filter expression.
These errors went undetected in part because these conversion functions
returned unique_ptr<Expression> values (or vectors thereof), using
{nullptr} to represent a parsing error, but the core expression classes
expect unique_ptr<Expression> that are never null.
This changes over to using expression::ParseResult (aka
optional<unique_ptr<Expression>>), to represent conversion failure
the same way we do in the rest of the expression system.
* Fix clang 3.8 / gcc 4.9 issue
GLIBC 2.27 added new versioned symbols of powf and logf, while the double versions of pow and log remained stable.
Prefer the double version to avoid introducing a dependency on a newer version of GLIBC than strictly necessary.
See https://lists.gnu.org/archive/html/info-gnu/2018-02/msg00000.html
Makes `["match", ["get", k], label, match, otherwise]` equivalent to `["case", ["==", ["get", k], label], match, otherwise]`. This changes the behavior of match expressions where the runtime type of the input does not match the type of the labels: previously such expressions produced a runtime type error and then fell back to the property default value; now they produce the fallback value from the match expression.
