import type { ExpressionOrValue } from '../expression.js';
import type { ArgumentValue } from './argument.js';

/** 表示一个全局变量 */
export type Variable<T extends ArgumentValue = ArgumentValue> = {
    /** 唯一 key */
    key: string;
    /** 变量值 */
    value: ExpressionOrValue<T>;
};

/** 检查是否为 `Variable` */
export function isVariable(obj: unknown): obj is Variable {
    if (obj == null || typeof obj != 'object') return false;
    if ('condition' in obj || 'description' in obj || 'type' in obj) return false;
    const v = obj as Variable;
    return typeof v.key == 'string' && 'value' in v;
}