feat: Support file as argument and better error message

bin/main.ml

@@ -3,16 +3,34 @@
 open Printf
 open Ast.Print
 
-let () =
+let get_lexbuf () =
+  if Array.length Sys.argv > 1 then (
+    let lexbuf = Lexing.from_channel (open_in Sys.argv.(1)) in
+    Lexing.set_filename lexbuf Sys.argv.(1);
+    lexbuf)
+  else
     let lexbuf = Lexing.from_channel stdin in
+    Lexing.set_filename lexbuf "stdin";
+    lexbuf
+
+let () =
+  let lexbuf = get_lexbuf () in
   let res =
     try Parser.main Lexer.token lexbuf with
     | Lexer.Error c ->
-        fprintf stderr "Lexical error at line %d: Unknown character '%c'\n"
-          lexbuf.lex_curr_p.pos_lnum c;
+        let file_name = lexbuf.lex_curr_p.pos_fname
+        and line_num = lexbuf.lex_curr_p.pos_lnum
+        and col_num = lexbuf.lex_curr_p.pos_cnum - lexbuf.lex_curr_p.pos_bol in
+        fprintf stderr "Fichier \"%s\", ligne %d, colonne %d\n%s: %s\n"
+          file_name line_num col_num "Erreur lexicale"
+          ("Caractère '" ^ String.make 1 c ^ "' inconnu");
         exit 1
     | Parser.Error ->
-        fprintf stderr "Parse error at line %d:\n" lexbuf.lex_curr_p.pos_lnum;
+        let file_name = lexbuf.lex_curr_p.pos_fname
+        and line_num = lexbuf.lex_curr_p.pos_lnum
+        and col_num = lexbuf.lex_curr_p.pos_cnum - lexbuf.lex_curr_p.pos_bol in
+        fprintf stderr "Fichier \"%s\", ligne %d, colonne %d\n%s: %s\n"
+          file_name line_num col_num "Erreur syntaxique" "Syntaxe incorrecte";
         exit 1
   in
   let _ = res in

lib/ast/print.ml

@@ -71,14 +71,14 @@ let string_of_source_file = function
       let stmt_strings = List.map string_of_statement stmts in
       "SourceFile([" ^ String.concat ", " stmt_strings ^ "])"
 
-(** The signature of the module [PRINT]. *)
+(** The signature of the module [Print]. *)
 module type Print = sig
-  val string_of_type : Syntax._type -> string
-  val string_of_binary_operator : Syntax.binary_operator -> string
-  val string_of_unary_operator : Syntax.unary_operator -> string
-  val string_of_literal : Syntax.literal -> string
-  val string_of_expression : Syntax.expression -> string
-  val string_of_variable_declaration : Syntax.variable_declaration -> string
-  val string_of_statement : Syntax.statement -> string
-  val string_of_source_file : Syntax.source_file -> string
+  val string_of_type : _type -> string
+  val string_of_binary_operator : binary_operator -> string
+  val string_of_unary_operator : unary_operator -> string
+  val string_of_literal : literal -> string
+  val string_of_expression : expression -> string
+  val string_of_variable_declaration : variable_declaration -> string
+  val string_of_statement : statement -> string
+  val string_of_source_file : source_file -> string
 end

lib/lexer.mll

@@ -4,9 +4,8 @@
   exception Error of char
 }
 
-let line_comment = "//" [^ '\n']*
-let block_comment = "/*" [^'.']* "*/"
-let comment = line_comment | block_comment
+let line_comment = "//" [^'.']*'\n'
+ let block_comment = "/*" [^'.']* "*/"
 
 let letter = ['a'-'z' 'A'-'Z']
 let digit = ['0'-'9']
@@ -20,8 +19,12 @@ let char = "'" [^'.'] "'"
 let string = '"' [^'.']*  '"'
 
 rule token = parse
-   |  [' ' '\t'] | comment { token lexbuf }
-   | ['\n'] { Lexing.new_line lexbuf; token lexbuf }
+   |  ' ' | '\t' { token lexbuf }
+   | '\n' | line_comment { Lexing.new_line lexbuf; token lexbuf }
+   | block_comment as comment {
+     String.iter (fun c -> if c = '\n' then Lexing.new_line lexbuf) comment;
+     token lexbuf
+   }
 
    | '+' { PLUS }
    | '-' { MINUS }

test/ressources/test.🥐

@@ -1,26 +1,3 @@
-// Déclaration d'une variable de type entier
-var a: entier = 4 + 2 + 3 * 1;
+/*Hello, World!*/
 
-/*
-SourceFile([
-  VariableStatement([
-    VariableDeclaration(
-      Type_Integer,
-      Identifier("a"),
-      BinaryExpression(
-        Add,
-        BinaryExpression(
-          Add,
-          Literal(Integer(4)),
-          Literal(Integer(2))
-        ),
-        BinaryExpression(
-          Multiply,
-          Literal(Integer(3)),
-          Literal(Integer(1))
-        )
-      )
-    )
-  ])
-])
-*/
+var a = 1;