From 99defca21a05aeeb1c0c69f4d9a16d4fa8fd0742 Mon Sep 17 00:00:00 2001
From: Christian Rinderknecht <Christian.Rinderknecht@tezcore.com>
Date: Mon, 1 Apr 2019 20:59:37 +0200
Subject: [PATCH] Added alternate syntax for "case" constructs (both expression
 and instruction).

New syntax: case ... of [ ... ]
---
 src/ligo/ligo-parser/AST.ml                  | 28 +++++++--------
 src/ligo/ligo-parser/AST.mli                 |  4 +--
 src/ligo/ligo-parser/Parser.mly              | 36 ++++++++++++++------
 src/ligo/ligo-parser/Tests/crowdfunding.ligo |  4 +--
 4 files changed, 43 insertions(+), 29 deletions(-)

diff --git a/src/ligo/ligo-parser/AST.ml b/src/ligo/ligo-parser/AST.ml
index cf2de7662..03c0af8d1 100644
--- a/src/ligo/ligo-parser/AST.ml
+++ b/src/ligo/ligo-parser/AST.ml
@@ -419,12 +419,12 @@ and set_membership = {
 }
 
 and 'a case = {
-  kwd_case   : kwd_case;
-  expr       : expr;
-  kwd_of     : kwd_of;
-  lead_vbar  : vbar option;
-  cases      : ('a case_clause reg, vbar) nsepseq reg;
-  kwd_end    : kwd_end
+  kwd_case  : kwd_case;
+  expr      : expr;
+  opening   : opening;
+  lead_vbar : vbar option;
+  cases     : ('a case_clause reg, vbar) nsepseq reg;
+  closing   : closing
 }
 
 and 'a case_clause = {
@@ -1111,14 +1111,14 @@ and print_if_clause = function
     print_token rbrace "}"
 
 and print_case_instr (node : instruction case) =
-  let {kwd_case; expr; kwd_of;
-       lead_vbar; cases; kwd_end} = node in
+  let {kwd_case; expr; opening;
+       lead_vbar; cases; closing} = node in
   print_token kwd_case "case";
   print_expr  expr;
-  print_token kwd_of "of";
+  print_opening "of" opening;
   print_token_opt lead_vbar "|";
   print_cases_instr cases;
-  print_token kwd_end "end"
+  print_closing closing
 
 and print_token_opt = function
          None -> fun _ -> ()
@@ -1222,14 +1222,14 @@ and print_expr = function
 | EPar    e -> print_par_expr e
 
 and print_case_expr (node : expr case) =
-  let {kwd_case; expr; kwd_of;
-       lead_vbar; cases; kwd_end} = node in
+  let {kwd_case; expr; opening;
+       lead_vbar; cases; closing} = node in
   print_token kwd_case "case";
   print_expr  expr;
-  print_token kwd_of "of";
+  print_opening "of" opening;
   print_token_opt lead_vbar "|";
   print_cases_expr cases;
-  print_token kwd_end "end"
+  print_closing closing
 
 and print_cases_expr {value; _} =
   print_nsepseq "|" print_case_clause_expr value
diff --git a/src/ligo/ligo-parser/AST.mli b/src/ligo/ligo-parser/AST.mli
index cf8ac5ddc..306ceb94d 100644
--- a/src/ligo/ligo-parser/AST.mli
+++ b/src/ligo/ligo-parser/AST.mli
@@ -405,10 +405,10 @@ and set_membership = {
 and 'a case = {
   kwd_case  : kwd_case;
   expr      : expr;
-  kwd_of    : kwd_of;
+  opening   : opening;
   lead_vbar : vbar option;
   cases     : ('a case_clause reg, vbar) nsepseq reg;
-  kwd_end   : kwd_end
+  closing   : closing
 }
 
 and 'a case_clause = {
diff --git a/src/ligo/ligo-parser/Parser.mly b/src/ligo/ligo-parser/Parser.mly
index ca79c8934..ae0e8f088 100644
--- a/src/ligo/ligo-parser/Parser.mly
+++ b/src/ligo/ligo-parser/Parser.mly
@@ -686,18 +686,22 @@ case_instr:
     let value  = {
       kwd_case  = $1;
       expr      = $2;
-      kwd_of    = $3;
+      opening   = Kwd $3;
       lead_vbar = $4;
       cases     = $5;
-      kwd_end   = $6}
-    in {region; value}}
-(*| Case expr LBRACKET option(VBAR) case_instr RBRACKET {
-    let region = cover $1 $6 in
-    let value  = {
-      k
-      }
+      closing   = End $6}
+    in {region; value}
   }
- *)
+| Case expr Of LBRACKET option(VBAR) cases_instr RBRACKET {
+    let region = cover $1 $7 in
+    let value  = {
+      kwd_case  = $1;
+      expr      = $2;
+      opening   = KwdBracket ($3,$4);
+      lead_vbar = $5;
+      cases     = $6;
+      closing   = RBracket $7}
+    in {region; value}}
 
 cases_instr:
   nsepseq(case_clause_instr,VBAR) {
@@ -790,10 +794,20 @@ case_expr:
     let value : expr case = {
       kwd_case  = $1;
       expr      = $2;
-      kwd_of    = $3;
+      opening   = Kwd $3;
       lead_vbar = $4;
       cases     = $5;
-      kwd_end   = $6}
+      closing   = End $6}
+    in ECase {region; value}}
+| Case expr Of LBRACKET option(VBAR) cases_expr RBRACKET {
+    let region = cover $1 $7 in
+    let value  = {
+      kwd_case  = $1;
+      expr      = $2;
+      opening   = KwdBracket ($3,$4);
+      lead_vbar = $5;
+      cases     = $6;
+      closing   = RBracket $7}
     in ECase {region; value}}
 
 cases_expr:
diff --git a/src/ligo/ligo-parser/Tests/crowdfunding.ligo b/src/ligo/ligo-parser/Tests/crowdfunding.ligo
index 34d45595a..834f319ca 100644
--- a/src/ligo/ligo-parser/Tests/crowdfunding.ligo
+++ b/src/ligo/ligo-parser/Tests/crowdfunding.ligo
@@ -17,11 +17,11 @@ entrypoint contribute (storage store : store;
     if now > store.deadline then
       fail "Deadline passed";
     else
-      case store.backers[sender] of
+      case store.backers[sender] of [
         None -> store.backers[sender] := Some (amount)
 //        None -> patch store.backers with map sender -> amount end
       |    _ -> skip
-      end
+      ]
   } with (store, operations)
 
 entrypoint withdraw (storage store : store; const sender : address)