Redefine [parens] using [block]. Extract global parameters.

generator/print_coq.ml

@@ -3,6 +3,16 @@ open Coq
 
 (* -------------------------------------------------------------------------- *)
 
+(* Global parameters. *)
+
+let indentation =
+  2
+
+let width =
+  80
+
+(* -------------------------------------------------------------------------- *)
+
 (* Various fixed elements. *)
 
 let arrow =
@@ -30,7 +40,7 @@ let quote =
 let app d1 d2 =
   (* The following definition would reject a large argument on a line of
      its own, indented: *)
-  (* group (d1 ^^ nest 2 (break 1 ^^ d2)) *)
+  (* group (d1 ^^ nest indentation (break 1 ^^ d2)) *)
   (* However, that would be redundant with the fact that large arguments
      are usually parenthesized, and we already break lines and indent
      within the parentheses. So, the following suffices: *)
@@ -50,6 +60,9 @@ let apps ds =
 let block n opening contents closing =
   group (opening ^^ nest n (contents) ^^ closing)
 
+let block =
+  block indentation
+
 (* -------------------------------------------------------------------------- *)
 
 (* Parentheses with indentation. *)
@@ -58,10 +71,10 @@ let block n opening contents closing =
    opening and closing parentheses alone on a line and indenting the content. *)
 
 let parens d =
-  group (
-    nest 2 (lparen ^^ break 0 ^^ d) ^^
-    break 0 ^^ rparen
-  )
+  block
+    lparen
+    (break 0 ^^ d)
+    (break 0 ^^ rparen)
 
 (* -------------------------------------------------------------------------- *)
 
@@ -136,21 +149,21 @@ and expr2 = function
 
 and expr3 = function
   | Coq_lettuple (es, e1, e2) ->
-      block 2
+      block
         (string "let '" ^^ tuple expr es ^^ colonequals)
         (break 1 ^^ expr e1)
         (break 1 ^^ within)
       ^/^
       expr3 e2
   | Coq_forall ((x, e1), e2) ->
-      block 2
+      block
         (string "forall " ^^ string x ^^ colon)
         (break 1 ^^ expr e1 ^^ comma)
         empty
       ^/^
       expr3 e2
   | Coq_fun ((x, e1), e2) ->
-      block 2
+      block
         (string "fun" ^^ space ^^ string x ^^ colon)
         (break 1 ^^ expr e1)
         (break 1 ^^ doublearrow)
@@ -166,7 +179,6 @@ and expr e =
 
 let expr e : string =
   let b = Buffer.create 1024 in
-  PPrintEngine.ToBuffer.pretty 0.9 80 b (expr e);
+  PPrintEngine.ToBuffer.pretty 0.9 width b (expr e);
   Buffer.contents b
 
-(* TEMPORARY allow choosing the width *)