53 lines
1.7 KiB
Rust
53 lines
1.7 KiB
Rust
|
/* Copyright (C) 2021 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 <http://www.gnu.org/licenses/>.
|
||
|
|
*/
|
||
|
|
|
||
|
|
use crate::segment::{Ctr, Seg};
|
||
|
|
use crate::sym::{SymTable};
|
||
|
|
|
||
|
|
// Some essential operations below
|
||
|
|
pub fn append_callback (ast: &Seg, _syms: &mut SymTable) -> Result<Ctr, String> {
|
||
|
|
// if car is a list, append cdr
|
||
|
|
// otherwise create a list out of all arguments
|
||
|
|
if let Ctr::Seg(ref s) = *ast.car {
|
||
|
|
let mut temp = s.clone();
|
||
|
|
temp.append(ast.cdr.clone());
|
||
|
|
Ok(Ctr::Seg(temp))
|
||
|
|
} else {
|
||
|
|
let mut temp = Seg::new();
|
||
|
|
let mut car_iter = &ast.car;
|
||
|
|
let mut cdr_iter = &ast.cdr;
|
||
|
|
loop {
|
||
|
|
temp.append(car_iter.clone());
|
||
|
|
if let Ctr::Seg(ref s) = **cdr_iter {
|
||
|
|
car_iter = &s.car;
|
||
|
|
cdr_iter = &s.cdr;
|
||
|
|
} else {
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
Ok(Ctr::Seg(temp))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
pub fn expand_callback (ast: &Seg, _syms: &mut SymTable) -> Result<Ctr, String> {
|
||
|
|
if let Ctr::Seg(_) = *ast.car {
|
||
|
|
Ok(*ast.car.clone())
|
||
|
|
} else {
|
||
|
|
Err("non list passed to expand!".to_string())
|
||
|
|
}
|
||
|
|
}
|