import * as React from "react";
import { ExprOr } from "../../api/ol-style-contracts";
export declare function contrast(colorHex: string | undefined, threshold?: number): string;
export declare type ExprEditorProps<T> = {
    locale: string;
    value?: ExprOr<T>;
    onChange: (value: ExprOr<T> | undefined) => void;
};
export declare const NumberExprEditor: React.FC<ExprEditorProps<number> & {
    min?: number;
    max?: number;
}>;
export declare const SliderExprEditor: React.FC<ExprEditorProps<number> & {
    min?: number;
    max?: number;
    labelStepSize?: number;
}>;
export declare const StringExprEditor: React.FC<ExprEditorProps<string>>;
export declare const BooleanExprEditor: React.FC<ExprEditorProps<boolean>>;
export declare const ColorExprEditor: React.FC<ExprEditorProps<string>>;
