added If, And, Or

lib/stmt.ml

@@ -5,40 +5,47 @@ type stmt =
   | Print of expr_node
   | VarDecl of { name : string; init : expr_node option }
   | Block of stmt_node list
+  | If of { cond : expr_node; then_ : stmt_node; else_ : stmt_node option }
 
 and stmt_node = { stmt : stmt; pos : Error.code_pos }
 
 let rec show_stmt ?(indent = 0) stmt =
   let indent_s = String.make indent ' ' in
+  let show_expr_ind ?(depth = 2) = show_expr ~indent:(indent + depth) in
+  let show_stmt_ind ?(depth = 2) = show_stmt ~indent:(indent + depth) in
   match stmt with
-  | Expr expr -> indent_s ^ "Expr\n" ^ show_expr ~indent:(indent + 2) expr.expr
-  | Print expr -> indent_s ^ "Print\n" ^ show_expr ~indent:(indent + 2) expr.expr
+  | Expr expr -> indent_s ^ "Expr\n" ^ show_expr_ind expr.expr
+  | Print expr -> indent_s ^ "Print\n" ^ show_expr_ind expr.expr
   | VarDecl { name; init } -> (
       indent_s ^ "Var " ^ name
-      ^
-      match init with Some init -> " = \n" ^ show_expr ~indent:(indent + 2) init.expr | None -> "")
+      ^ match init with Some init -> " = \n" ^ show_expr_ind init.expr | None -> "")
   | Block stmts ->
       let stmts_s =
-        List.fold_left
-          (fun acc stmt -> acc ^ show_stmt ~indent:(indent + 2) stmt.stmt ^ "\n")
-          "" stmts
+        List.fold_left (fun acc stmt -> acc ^ show_stmt_ind stmt.stmt ^ "\n") "" stmts
       in
       "Block" ^ stmts_s ^ "End"
+  | If { cond; then_; else_ } ->
+      let cond_s = show_expr_ind cond.expr in
+      let then_s = show_stmt_ind ~depth:4 then_.stmt in
+      let else_s = Option.map (fun stmt -> show_stmt_ind ~depth:4 stmt.stmt) else_ in
+      indent_s ^ "If\n" ^ cond_s ^ "\n" ^ indent_s ^ "  Then\n" ^ then_s
+      ^ if Option.is_some else_s then "\n" ^ indent_s ^ "  Else\n" ^ Option.get else_s else ""
 
 let show_stmt_node stmt_node = show_stmt stmt_node.stmt
+let make_stmt_node (pos : Error.code_pos) (stmt : stmt) : stmt_node = { stmt; pos }
 
 let make_expr_stmt (pos : Error.code_pos) (expr : expr_node) : stmt_node =
-  let stmt = Expr expr in
-  { stmt; pos }
+  Expr expr |> make_stmt_node pos
 
 let make_print (pos : Error.code_pos) (expr : expr_node) : stmt_node =
-  let stmt = Print expr in
-  { stmt; pos }
+  Print expr |> make_stmt_node pos
 
 let make_var_decl (pos : Error.code_pos) (name : string) (init : expr_node option) =
-  let stmt = VarDecl { name; init } in
-  { stmt; pos }
+  VarDecl { name; init } |> make_stmt_node pos
 
 let make_block (pos : Error.code_pos) (stmts : stmt_node list) : stmt_node =
-  let stmt = Block stmts in
-  { stmt; pos }
+  Block stmts |> make_stmt_node pos
+
+let make_if (pos : Error.code_pos) (cond : expr_node) (then_ : stmt_node) (else_ : stmt_node option)
+    =
+  If { cond; then_; else_ } |> make_stmt_node pos