diff options
Diffstat (limited to 'src/Mapbox/Expression.elm')
| -rw-r--r-- | src/Mapbox/Expression.elm | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/src/Mapbox/Expression.elm b/src/Mapbox/Expression.elm index 6a9d9f7..af8298c 100644 --- a/src/Mapbox/Expression.elm +++ b/src/Mapbox/Expression.elm @@ -37,6 +37,7 @@ module Mapbox.Expression , has , count , length + , featureState , geometryType , id , properties @@ -61,7 +62,7 @@ module Mapbox.Expression , conditionally , matchesStr , matchesFloat - , coallesce + , coalesce , interpolate , Interpolation(..) , step @@ -198,7 +199,7 @@ You can also use these functions to explicitly cast to a particular type: ### Feature data -@docs geometryType, id, properties, getProperty, hasProperty +@docs featureState, geometryType, id, properties, getProperty, hasProperty ### Decision @@ -217,7 +218,7 @@ Logical operators: Control flow: -@docs ifElse, conditionally, matchesStr, matchesFloat, coallesce +@docs ifElse, conditionally, matchesStr, matchesFloat, coalesce ### Ramps, scales, curves @@ -268,7 +269,7 @@ Note however, that while being a strictly typed language, it has slighlty differ - There is only a single number type. I have denoted it `Float`. You will notice that the `int` function takes an Elm int value and converts it to an `Expression expr Float`. - - All values may be `null`. There is no `Maybe` type. You can use the `coallesce` function to handle this. + - All values may be `null`. There is no `Maybe` type. You can use the `coalesce` function to handle this. - There is no distinction between `List`, `Array`, and tuples. Hence all collections are labeled as `Array`. - Dictionaries are called `Object`. The keys are always `String`, but the values can be of mixed types. Hence retrieving values from them makes code untyped. @@ -822,6 +823,13 @@ call name args = Expression (Json.Encode.list (Json.Encode.string name :: args)) +{-| Retrieves a property value from the current feature's state. Returns null if the requested property is not present on the feature's state. A feature's state is not part of the GeoJSON or vector tile data, and must be set programmatically on each feature. Note that `featureState` can only be used with paint properties that support data-driven styling. +-} +featureState : Expression exprType String -> Expression DataExpression any +featureState = + call1 "feature-state" + + {-| Gets the feature's geometry type: Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon. -} geometryType : Expression DataExpression String @@ -993,9 +1001,9 @@ any = {-| Evaluates each expression in turn until the first non-null value is obtained, and returns that value. -} -coallesce : List (Expression exprType outputType) -> Expression exprType outputType -coallesce = - calln "coallesce" +coalesce : List (Expression exprType outputType) -> Expression exprType outputType +coalesce = + calln "coalesce" {-| The ternary operator: |