import { type Scanner } from "@ark/util";
import type { Comparator } from "../reduce/shared.ts";
export declare const terminatingChars: {
    readonly " ": 1;
    readonly "\n": 1;
    readonly "\t": 1;
    readonly "<": 1;
    readonly ">": 1;
    readonly "=": 1;
    readonly "|": 1;
    readonly "&": 1;
    readonly ")": 1;
    readonly "[": 1;
    readonly "%": 1;
    readonly ",": 1;
    readonly ":": 1;
    readonly "?": 1;
    readonly "#": 1;
};
export type TerminatingChar = keyof typeof terminatingChars;
export declare const finalizingLookaheads: {
    readonly ">": 1;
    readonly ",": 1;
    readonly "": 1;
    readonly "=": 1;
    readonly "?": 1;
};
export type FinalizingLookahead = keyof typeof finalizingLookaheads;
export declare const lookaheadIsFinalizing: (lookahead: string, unscanned: string) => lookahead is ">" | "," | "=" | "?";
export type lookaheadIsFinalizing<lookahead extends string, unscanned extends string> = lookahead extends ">" ? unscanned extends `=${infer nextUnscanned}` ? nextUnscanned extends `=${string}` ? true : false : Scanner.skipWhitespace<unscanned> extends ("" | `${TerminatingChar}${string}`) ? true : false : lookahead extends "=" ? unscanned extends `=${string}` ? false : true : lookahead extends "," | "?" ? true : false;
export type InfixToken = Comparator | "|" | "&" | "%" | ":" | "=>" | "|>" | "#" | "@" | "=";
export type PostfixToken = "[]" | "?";
export type OperatorToken = InfixToken | PostfixToken;