feat: everything

parser/src/parser.rs

@@ -15,6 +15,20 @@ fn convert_span(span: Span) -> Loc {
     let (x2, y2) = span.end_pos().line_col();
     Loc::new(x1, y1, x2, y2)
 }
+fn build_term_from_expr(
+    pair: Pair<Rule>,
+    known_vars: &mut VecDeque<String>,
+    //defined_vars: issue #18 TODO use a hash map of known variables
+) -> Result<Term, Box<Error<Rule>>> {
+    match pair.as_rule() {
+        Rule::Prop => Ok(Term::Prop),
+        Rule::Type => Ok(Term::Type(
+            pair.into_inner()
+                .as_str()
+                .parse::<usize>()
+                .unwrap()
+                .into(),
+        )),
 
 /// build terms from errorless pest's output
 fn build_term_from_expr(pair: Pair<Rule>, known_vars: &mut VecDeque<String>) -> Term {