import type { ExprValue } from '../types/expr-value';
import { ExpressionDef } from '../types/expression-def';
import type { FieldSpace } from '../types/field-space';
import { MalloyElement } from '../types/malloy-element';
export declare class Pick extends ExpressionDef {
    readonly choices: PickWhen[];
    readonly elsePick?: ExpressionDef | undefined;
    elementType: string;
    constructor(choices: PickWhen[], elsePick?: ExpressionDef | undefined);
    requestExpression(fs: FieldSpace): ExprValue | undefined;
    apply(fs: FieldSpace, op: string, expr: ExpressionDef): ExprValue;
    getExpression(fs: FieldSpace): ExprValue;
}
export declare class PickWhen extends MalloyElement {
    readonly pick: ExpressionDef | undefined;
    readonly when: ExpressionDef;
    elementType: string;
    constructor(pick: ExpressionDef | undefined, when: ExpressionDef);
}