implement unparse()

src/lib.rs

@@ -4,6 +4,7 @@ pub mod dict;
 pub mod term;
 pub mod lexer;
 pub mod parser;
+pub mod unparser;
 pub mod curry;
 pub mod lnf;
 pub mod subtype;

src/unparser.rs

@@ -0,0 +1,47 @@
+use crate::{dict::*, term::*};
+
+//<<<<>>>><<>><><<>><<<*>>><<>><><<>><<<<>>>>\\
+
+impl TypeDict {
+    pub fn unparse(&self, t: &TypeTerm) -> String {
+        match t {
+            TypeTerm::TypeID(id) => self.get_typename(id).unwrap(),
+            TypeTerm::Num(n) => format!("{}", n),
+            TypeTerm::Char(c) => match c {
+                '\0' => "'\\0'".into(),
+                '\n' => "'\\n'".into(),
+                '\t' => "'\\t'".into(),
+                '\'' => "'\\''".into(),
+                c => format!("'{}'", c)
+            },
+            TypeTerm::Ladder(rungs) => {
+                let mut s = String::new();
+                let mut first = true;
+                for r in rungs.iter() {
+                    if !first {
+                        s.push('~');
+                    }
+                    first = false;
+                    s.push_str(&mut self.unparse(r));
+                }
+                s
+            }
+            TypeTerm::App(args) => {
+                let mut s = String::new();
+                s.push('<');
+                let mut first = true;
+                for r in args.iter() {
+                    if !first {
+                        s.push(' ');
+                    }
+                    first = false;
+                    s.push_str(&mut self.unparse(r));
+                }
+                s.push('>');
+                s
+            }
+        }
+    }
+}
+
+//<<<<>>>><<>><><<>><<<*>>><<>><><<>><<<<>>>>\\