Remove references to safe-string in the stdlib

Author: hhugo

stdlib/.depend

@@ -475,14 +475,12 @@ stdlib__Lazy.cmi : lazy.mli \
     camlinternalLazy.cmi
 stdlib__Lexing.cmo : lexing.ml \
     stdlib__Sys.cmi \
-    stdlib__String.cmi \
     stdlib__Int.cmi \
     stdlib__Bytes.cmi \
     stdlib__Array.cmi \
     stdlib__Lexing.cmi
 stdlib__Lexing.cmx : lexing.ml \
     stdlib__Sys.cmx \
-    stdlib__String.cmx \
     stdlib__Int.cmx \
     stdlib__Bytes.cmx \
     stdlib__Array.cmx \

stdlib/bytes.mli

@@ -332,9 +332,9 @@ val ends_with :
     This section describes unsafe, low-level conversion functions
     between [bytes] and [string]. They do not copy the internal data;
     used improperly, they can break the immutability invariant on
-    strings provided by the [-safe-string] option. They are available for
-    expert library authors, but for most purposes you should use the
-    always-correct {!to_string} and {!of_string} instead.
+    strings. They are available for expert library authors, but for
+    most purposes you should use the always-correct {!to_string} and
+    {!of_string} instead.
 *)
 
 val unsafe_to_string : bytes -> string

stdlib/bytesLabels.mli

@@ -332,9 +332,9 @@ val ends_with :
     This section describes unsafe, low-level conversion functions
     between [bytes] and [string]. They do not copy the internal data;
     used improperly, they can break the immutability invariant on
-    strings provided by the [-safe-string] option. They are available for
-    expert library authors, but for most purposes you should use the
-    always-correct {!to_string} and {!of_string} instead.
+    strings. They are available for expert library authors, but for
+    most purposes you should use the always-correct {!to_string} and
+    {!of_string} instead.
 *)
 
 val unsafe_to_string : bytes -> string

stdlib/lexing.ml

@@ -163,10 +163,13 @@ let from_channel ?with_positions ic =
   from_function ?with_positions (fun buf n -> input ic buf 0 n)
 
 let from_string ?(with_positions = true) s =
+  (* We can't use [Bytes.unsafe_of_string] here,
+     [lex_buffer] is exported in the mli, one can mutate
+     it outside this module. *)
+  let lex_buffer = Bytes.of_string s in
   { refill_buff = (fun lexbuf -> lexbuf.lex_eof_reached <- true);
-    lex_buffer = Bytes.of_string s; (* have to make a copy for compatibility
-                                       with unsafe-string mode *)
-    lex_buffer_len = String.length s;
+    lex_buffer;
+    lex_buffer_len = Bytes.length lex_buffer;
     lex_abs_pos = 0;
     lex_start_pos = 0;
     lex_curr_pos = 0;

stdlib/string.mli

@@ -347,8 +347,7 @@ val rindex_opt : string -> char -> int option
 
 val to_seq : t -> char Seq.t
 (** [to_seq s] is a sequence made of the string's characters in
-    increasing order. In ["unsafe-string"] mode, modifications of the string
-    during iteration will be reflected in the sequence.
+    increasing order.
 
     @since 4.07 *)
 

stdlib/stringLabels.mli

@@ -347,8 +347,7 @@ val rindex_opt : string -> char -> int option
 
 val to_seq : t -> char Seq.t
 (** [to_seq s] is a sequence made of the string's characters in
-    increasing order. In ["unsafe-string"] mode, modifications of the string
-    during iteration will be reflected in the sequence.
+    increasing order.
 
     @since 4.07 *)