Add test file, implement and/or/not, prepare for proper compound proc

src/primitives.rs

@@ -1,4 +1,5 @@
 use crate::interpreter::has_tag;
+use crate::interpreter::is_true;
 use crate::parser::make_symbol;
 use crate::parser::Datum;
 use crate::parser::Datum::*;
@@ -89,6 +90,44 @@ pub fn lt(args: Vec<Datum>) -> Datum {
     }
 }
 
+pub fn or(args: Vec<Datum>) -> Datum {
+    if args.len() == 1 {
+        Boolean(false)
+    } else {
+        for i in 1..args.len() {
+            if is_true(&args[i]) {
+                return args[i].clone();
+            }
+        }
+        Boolean(false)
+    }
+}
+
+pub fn and(args: Vec<Datum>) -> Datum {
+    if args.len() == 1 {
+        Boolean(true)
+    } else {
+        for i in 1..args.len() {
+            if !is_true(&args[i]) {
+                return Boolean(false);
+            }
+        }
+        args[args.len() - 1].clone()
+    }
+}
+
+pub fn not(args: Vec<Datum>) -> Datum {
+    if args.len() != 2 {
+        panic!("NOT -- takes one argument");
+    } else {
+        if is_true(&args[1]) {
+            Boolean(false)
+        } else {
+            Boolean(true)
+        }
+    }
+}
+
 pub fn display(args: Vec<Datum>) -> Datum {
     for i in 1..args.len() {
         print!("{}", args[i]);