variable export and entire config system

src/config.rs

@@ -0,0 +1,74 @@
+/* relish: versatile lisp shell
+ * 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::vars::{VTable, define};
+use crate::func::{FTable, Args, Function, Operation, func_declare};
+use crate::segment::{Ast, Ctr};
+use crate::lex::lex;
+use crate::eval::eval;
+use std::rc::Rc;
+use std::cell::RefCell;
+use std::fs;
+
+pub fn configure(filename: String, vars: Rc<RefCell<VTable>>, funcs: Rc<RefCell<FTable>>) {
+    define(vars.clone(), String::from("CFG_RELISH_POSIX"), Rc::new(Ctr::String(String::from("1"))));
+    define(vars.clone(), String::from("CFG_RELISH_ENV"), Rc::new(Ctr::String(String::from("1"))));
+    func_declare(funcs.clone(), Rc::new(RefCell::new(Function{
+        name: String::from("CFG_RELISH_PROMPT"),
+        loose_syms: false,
+        eval_lazy: false,
+        args: Args::Lazy(0),
+        function: Operation::Internal(
+            |_: Ast, _: Rc<RefCell<VTable>>, _: Rc<RefCell<FTable>>| -> Ctr {
+                print!("λ ");
+                return Ctr::None;
+            }
+        )
+    })));
+
+    match fs::read_to_string(filename) {
+        Err(s) => {
+            eprintln!("Couldnt open configuration file: {}", s);
+            return
+        },
+
+        Ok(raw_config) => {
+            match lex(raw_config) {
+                Err(s) => {
+                    println!("Error in configuration: {}", s);
+                    return
+                },
+
+                Ok(config) => {
+                    match eval(config, vars, funcs, false) {
+                        Err(s) => {
+                            println!("Error in applying configuration: {}", s);
+                            return
+                        },
+
+                        Ok(ctr) => {
+                            match ctr {
+                                Ctr:: String(s) => println!("{}", s),
+                                _ => ()
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+}