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/*
 * parsing/condition.rs
 *
 * ftml - Library to parse Wikidot text
 * Copyright (C) 2019-2024 Wikijump Team
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

use super::token::Token;

/// Represents a condition on a parse state.
///
/// It takes a parser state and determines if it matches
/// the condition described by this structure, returning
/// a boolean as appropriate.
#[derive(Debug, Copy, Clone)]
pub enum ParseCondition {
    /// Condition is valid if the current token matches.
    CurrentToken(Token),

    /// Condition is valid if current and next tokens match.
    TokenPair(Token, Token),
}

impl ParseCondition {
    #[inline]
    pub fn current(token: Token) -> Self {
        ParseCondition::CurrentToken(token)
    }

    #[inline]
    pub fn token_pair(current: Token, next: Token) -> Self {
        ParseCondition::TokenPair(current, next)
    }
}