/*   SHS: Syntactically Homogeneous Shell
 *   Copyright (C) 2019  Aidan Hahn
 *
 *   This program is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU 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 General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

package ast

type VarTable map[string]*Token

func (VarTable vt) GetVar(arg string) *Token {
    val, ok := vt[arg]
    if !ok {
        return nil
    }

    return val
}

// Library represents variables defined in inner scope
// It is assumed library is ordered from innermost scope to outermost scope
func GetVar(arg string, library []VarTable) *Token {
    var res *Token
    res = nil
    for i := 0; i < len(library); i += 1 {
        res = library[i].GetVar(arg)
        if res != nil {
            // TODO: Log scope res was found in?
            break
        }
    }

    return res
}