import { In, Out, Predicate } from "../_interfaces";
import { Property } from "../Property";
/**
 * Filters Observable's values using the given predicate function. Supports
 * also filtering by `Property` - values are passed only when the property has
 * truthy value.
 *
 * @param predicateOrProperty Predicate function `x => boolean` or `Property` which is used to filter out value events
 * @param observable Source observable
 * @returns An `Observable` whose values pass the given predicate.
 *
 * @example
 *
 * // Filtering by predicate function
 * F.pipe(F.fromArray([1, 2, 3, 4]),
 *  F.filter(x => x % 2 === 0),
 *  F.log("Result"))
 * // logs: 2, 4, <end>
 *
 * // Filtering by Property
 * const isLoading: Property<boolean> = getLoading(document)
 * const clicksWhenNotLoading =
 *  F.pipe(F.fromEvents(document.getElementById("myButton"), "click"),
 *   F.filter(F.not(isLoading)))
 *
 * @public
 * @endomorphic
 */
export declare const filter: CurriedFilter;
interface CurriedFilter {
    <ObsType, ValueType>(predicateOrProperty: Predicate<ValueType> | Property<any>, observable: In<ObsType, ValueType>): Out<ObsType, ValueType>;
    <ValueType>(predicateOrProperty: Predicate<ValueType> | Property<any>): <ObsType>(observable: In<ObsType, ValueType>) => Out<ObsType, ValueType>;
}
export {};