From ff6db57f0931457738aaf11bedad36ea81d88003 Mon Sep 17 00:00:00 2001
From: David Binder <david.binder@uni-tuebingen.de>
Date: Sun, 24 Mar 2024 11:04:59 +0100
Subject: [PATCH] Implement prettyprinting of attributes (#169)

---
 lang/printer/src/tokens.rs |  1 +
 lang/printer/src/types.rs  |  6 ++++++
 lang/printer/src/ust.rs    | 19 ++++++++++++++++---
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/lang/printer/src/tokens.rs b/lang/printer/src/tokens.rs
index 0c76a45dfa..0917e66c63 100644
--- a/lang/printer/src/tokens.rs
+++ b/lang/printer/src/tokens.rs
@@ -7,6 +7,7 @@ pub const COLON: &str = ":";
 pub const DOT: &str = ".";
 pub const AT: &str = "@";
 pub const HOLE: &str = "?";
+pub const HASH: &str = "#";
 
 // Keywords
 
diff --git a/lang/printer/src/types.rs b/lang/printer/src/types.rs
index e64e0d4f19..38ca0fe64b 100644
--- a/lang/printer/src/types.rs
+++ b/lang/printer/src/types.rs
@@ -39,6 +39,12 @@ pub trait Print<'a> {
     }
 }
 
+impl<'a> Print<'a> for String {
+    fn print(&'a self, _cfg: &PrintCfg, alloc: &'a Alloc<'a>) -> Builder<'a> {
+        alloc.text(self)
+    }
+}
+
 pub trait PrintInCtx<'a> {
     type Ctx;
 
diff --git a/lang/printer/src/ust.rs b/lang/printer/src/ust.rs
index 9e7058c37e..741117d63a 100644
--- a/lang/printer/src/ust.rs
+++ b/lang/printer/src/ust.rs
@@ -96,6 +96,7 @@ impl<'a> PrintInCtx<'a> for Data {
 
         let head = doc
             .print(cfg, alloc)
+            .append(attr.print(cfg, alloc))
             .append(alloc.keyword(DATA))
             .append(alloc.space())
             .append(alloc.typ(name))
@@ -140,6 +141,7 @@ impl<'a> PrintInCtx<'a> for Codata {
 
         let head = doc
             .print(cfg, alloc)
+            .append(attr.print(cfg, alloc))
             .append(alloc.keyword(CODATA))
             .append(alloc.space())
             .append(alloc.typ(name))
@@ -175,7 +177,7 @@ impl<'a> Print<'a> for Def {
             return alloc.nil();
         }
 
-        let doc = doc.print(cfg, alloc);
+        let doc = doc.print(cfg, alloc).append(attr.print(cfg, alloc));
 
         let head = alloc
             .keyword(DEF)
@@ -200,7 +202,7 @@ impl<'a> Print<'a> for Codef {
             return alloc.nil();
         }
 
-        let doc = doc.print(cfg, alloc);
+        let doc = doc.print(cfg, alloc).append(attr.print(cfg, alloc));
 
         let head = alloc
             .keyword(CODEF)
@@ -223,7 +225,7 @@ impl<'a> Print<'a> for Let {
             return alloc.nil();
         }
 
-        let doc = doc.print(cfg, alloc);
+        let doc = doc.print(cfg, alloc).append(attr.print(cfg, alloc));
 
         let head = alloc
             .keyword(LET)
@@ -534,6 +536,17 @@ impl<'a> Print<'a> for Motive {
     }
 }
 
+impl<'a> Print<'a> for Attribute {
+    fn print(&'a self, cfg: &PrintCfg, alloc: &'a Alloc<'a>) -> Builder<'a> {
+        if self.attrs.is_empty() {
+            alloc.nil()
+        } else {
+            let p = print_comma_separated(&self.attrs, cfg, alloc);
+            alloc.text(HASH).append(p.brackets()).append(alloc.hardline())
+        }
+    }
+}
+
 impl<'a> Print<'a> for DocComment {
     fn print(&'a self, _cfg: &PrintCfg, alloc: &'a Alloc<'a>) -> Builder<'a> {
         let DocComment { docs } = self;