Extended conditional syntax for "else" clauses.

New syntax: if ... then ... else { ... }

AST.ml

@@ -406,15 +406,15 @@ and conditional = {
   kwd_if     : kwd_if;
   test       : test_expr;
   kwd_then   : kwd_then;
-  ifso       : ifso;
+  ifso       : if_clause;
   terminator : semi option;
   kwd_else   : kwd_else;
-  ifnot      : instruction
+  ifnot      : if_clause
 }
 
-and ifso =
-  ThenInstr of instruction
-| ThenBlock of (instructions * semi option) braces reg
+and if_clause =
+  ClauseInstr of instruction
+| ClauseBlock of (instructions * semi option) braces reg
 
 and test_expr =
   GenExpr of expr
@@ -759,6 +759,10 @@ let instr_to_region = function
 | Single SetRemove           {region; _}
 | Block                      {region; _} -> region
 
+let if_clause_to_region = function
+  ClauseInstr instr       -> instr_to_region instr
+| ClauseBlock {region; _} -> region
+
 let pattern_to_region = function
   PCons       {region; _}
 | PVar        {region; _}
@@ -1073,17 +1077,17 @@ and print_fail {kwd_fail; fail_expr} =
 and print_conditional node =
   let {kwd_if; test; kwd_then; ifso; terminator;
        kwd_else; ifnot} = node in
-  print_token       kwd_if "if";
-  print_test_expr   test;
-  print_token       kwd_then "then";
-  print_ifso        ifso;
-  print_terminator  terminator;
-  print_token       kwd_else "else";
-  print_instruction ifnot
+  print_token      kwd_if "if";
+  print_test_expr  test;
+  print_token      kwd_then "then";
+  print_if_clause  ifso;
+  print_terminator terminator;
+  print_token      kwd_else "else";
+  print_if_clause  ifnot
 
-and print_ifso = function
-  ThenInstr instr -> print_instruction instr
-| ThenBlock {value; _} ->
+and print_if_clause = function
+  ClauseInstr instr -> print_instruction instr
+| ClauseBlock {value; _} ->
     let {lbrace; inside; rbrace} = value in
     let instr, terminator = inside in
     print_token lbrace "{";

AST.mli

@@ -390,15 +390,15 @@ and conditional = {
   kwd_if     : kwd_if;
   test       : test_expr;
   kwd_then   : kwd_then;
-  ifso       : ifso;
+  ifso       : if_clause;
   terminator : semi option;
   kwd_else   : kwd_else;
-  ifnot      : instruction
+  ifnot      : if_clause
 }
 
-and ifso =
-  ThenInstr of instruction
-| ThenBlock of (instructions * semi option) braces reg
+and if_clause =
+  ClauseInstr of instruction
+| ClauseBlock of (instructions * semi option) braces reg
 
 and test_expr =
   GenExpr of expr
@@ -651,6 +651,7 @@ val local_decl_to_region : local_decl -> Region.t
 val path_to_region       : path -> Region.t
 val lhs_to_region        : lhs -> Region.t
 val rhs_to_region        : rhs -> Region.t
+val if_clause_to_region  : if_clause -> Region.t
 
 (* Printing *)
 

Parser.mly

@@ -580,8 +580,8 @@ proc_call:
   fun_call { $1 }
 
 conditional:
-  If test_expr Then ifso option(SEMI) Else instruction {
-    let region = cover $1 (instr_to_region $7) in
+  If test_expr Then if_clause option(SEMI) Else if_clause {
+    let region = cover $1 (if_clause_to_region $7) in
     let value = {
       kwd_if     = $1;
       test       = $2;
@@ -593,9 +593,9 @@ conditional:
     in {region; value}
   }
 
-ifso:
+if_clause:
   instruction {
-    ThenInstr $1
+    ClauseInstr $1
   }
 | LBRACE series(instruction,RBRACE) {
    let first, (others, terminator, closing) = $2 in
@@ -604,7 +604,7 @@ ifso:
      lbrace = $1;
      inside = (first, others), terminator;
      rbrace = closing} in
-   ThenBlock {value; region}
+   ClauseBlock {value; region}
   }
 
 test_expr:

Tests/crowdfunding.ligo

@@ -34,7 +34,7 @@ entrypoint withdraw (storage store : store; const sender : address)
              operations := [Transfer (owner, balance)];
         };
         else fail "Below target"
-      else fail "Too soon"
+      else { fail "Too soon"; }
     else skip
   end with (store, operations)