+ In_Initial_State function

source/library/encodings-generic_converters.ads

@@ -5,10 +5,18 @@ generic
 	type Target_String is array (Positive range <>) of Target_Character'Base;
 package Encodings.Generic_Converters with Pure is
 	type Converter is interface;
-	procedure Reset (State : in out Converter) is null;
-	--  Reset the converter to initial state (if any)
+
+	function In_Initial_State (This : Converter) return Boolean is abstract;
+	-- Query if converter in initial state, :
+	-- both source and target stream in their initial states
+	-- (as defined in their encoding specifiactions)
+	-- and there's no data in internal buffers that have to be output
+
+	procedure Reset (This : in out Converter) is null;
+	--  Reset the converter to the initial state (if any)
+
 	procedure Process (
-		State         : in out Converter;      -- Converter
+		This          : in out Converter;      -- Converter
 		Source        : in     Source_String;  -- Character sequence to convert
 		Source_Cursor :    out Natural;        -- Last character consumed by converter
 		Target        :    out Target_String;  -- Converted character sequence
@@ -16,7 +24,7 @@ package Encodings.Generic_Converters with Pure is
 	) is abstract;
 	--  Procedure converts a (part of) string
 	--  Procedure must consume whole source string or
-	--  fill whole target string.
+	--  fill whole target string (or both).
 	--  Source (Source_Cursor + 1 .. Source'Last)
 
 	--  Note: this is most basic conversion interface

source/library/encodings-generic_single_replace.adb

@@ -1,5 +1,8 @@
 package body Encodings.Generic_Single_Replace is
 
+	function In_Initial_State (State : Converter) return Boolean
+	is (State.S = Initial and then State.SI = Original'First);
+
 	procedure Reset (
 		This : in out Converter)
 	is

source/library/encodings-generic_single_replace.ads

@@ -18,6 +18,8 @@ package Encodings.Generic_Single_Replace is
 
 	type Converter is new Converter_Base.Converter with private;
 
+	overriding function In_Initial_State (State : Converter) return Boolean;
+
 	overriding procedure Reset (
 		This : in out Converter);
 

source/library/encodings-line_endings-generic_add_cr.adb

@@ -1,4 +1,15 @@
 package body Encodings.Line_Endings.Generic_Add_CR is
+
+	function In_Initial_State (State : Converter) return Boolean
+	is (State.State = Initial);
+
+	procedure Reset (
+		This : in out Converter)
+	is
+	begin
+		This.State := Initial;
+	end;
+
 	procedure Process (
 		This          : in out Converter;
 		Source        : in     String_Type;
@@ -38,4 +49,5 @@ package body Encodings.Line_Endings.Generic_Add_CR is
 			Target (Target_Cursor) := C;
 		end loop;
 	end Process;
+
 end Encodings.Line_Endings.Generic_Add_CR;

source/library/encodings-line_endings-generic_add_cr.ads

@@ -12,13 +12,19 @@ generic
 		Target_String    => String_Type); -- Base package
 package Encodings.Line_Endings.Generic_Add_CR is
 	type Converter is new Converter_Base.Converter with private;
+
+	overriding function In_Initial_State (State : Converter) return Boolean;
+
+	overriding procedure Reset (
+		This : in out Converter); -- Converter state
+
 	overriding procedure Process (
 		This          : in out Converter; -- Converter state
 		Source        : in     String_Type; -- String to be converted
 		Source_Cursor :    out Natural; -- Last index of source string read
 		Target        :    out String_Type; -- Converted string
-		Target_Cursor :    out Natural -- Last Index of destination string written
-	);
+		Target_Cursor :    out Natural); -- Last Index of destination string written
+
 private
 	type Converter_State is (
 		Initial,

source/library/encodings-line_endings-generic_strip_cr.adb

@@ -1,13 +1,24 @@
 with Ada.Assertions;
 use  Ada.Assertions;
 package body Encodings.Line_Endings.Generic_Strip_CR is
+
+	overriding function In_Initial_State (State : Converter) return Boolean
+	is (not State.Have_CR);
+
+	procedure Reset (
+		This : in out Converter)
+	is
+	begin
+		This.Have_CR := False;
+	end Reset;
+
 	procedure Process (
 		This          : in out Converter;
 		Source        : in     String_Type;
 		Source_Cursor :    out Natural;
 		Target        :    out String_Type;
-		Target_Cursor :    out Natural
-	) is
+		Target_Cursor :    out Natural)
+	is
 		C : Character_Type;
 	begin
 		Source_Cursor := Source'First - 1;
@@ -38,4 +49,5 @@ package body Encodings.Line_Endings.Generic_Strip_CR is
 			Source_Cursor := Source_Cursor + 1;
 		end loop;
 	end Process;
+
 end Encodings.Line_Endings.Generic_Strip_CR;

source/library/encodings-line_endings-generic_strip_cr.ads

@@ -12,13 +12,18 @@ generic
 		Target_String    => String_Type); -- Base package
 package Encodings.Line_Endings.Generic_Strip_CR is
 	type Converter is new Converter_Base.Converter with private;
+
+	overriding function In_Initial_State (State : Converter) return Boolean;
+
+	overriding procedure Reset (
+		This : in out Converter);
+
 	overriding procedure Process (
 		This          : in out Converter; -- Coder state
 		Source        : in     String_Type; -- String to be converted
 		Source_Cursor :    out Natural; -- Last index of source string read
 		Target        :    out String_Type; -- Converted string
-		Target_Cursor :    out Natural -- Last Index of destination string written
-	);
+		Target_Cursor :    out Natural); -- Last Index of destination string written
 private
 	type Converter is new Converter_Base.Converter with record
 		Have_CR : Boolean := False;

source/library/encodings-unicode-utf_16-from_utf_32.adb

@@ -1,5 +1,8 @@
 package body Encodings.Unicode.UTF_16.From_UTF_32 is
 
+	function In_Initial_State (State : Converter) return Boolean
+	is (State.Surrogate not in Low_Surrogate);
+
 	procedure Reset (State : in out Converter) is
 	begin
 		State.Surrogate := UTF_16_Character'Val (0);

source/library/encodings-unicode-utf_16-from_utf_32.ads

@@ -9,6 +9,8 @@ package Encodings.Unicode.UTF_16.From_UTF_32 is
 
 	type Converter is new Converters.Wide_Wide_to_Wide.Converter with private;
 
+	overriding function In_Initial_State (State : Converter) return Boolean;
+
 	overriding procedure Reset (State : in out Converter);
 
 	overriding procedure Process (

source/library/encodings-unicode-utf_32-from_utf_8.adb

@@ -1,5 +1,8 @@
 package body Encodings.Unicode.UTF_32.From_UTF_8 is
 
+	function In_Initial_State (State : Converter) return Boolean
+	is (State.L = 0);
+
 	procedure Reset (State : in out Converter) is
 	begin
 		State.L := 0;

source/library/encodings-unicode-utf_32-from_utf_8.ads

@@ -6,6 +6,8 @@ package Encodings.Unicode.UTF_32.From_UTF_8 is
 
 	type Converter is new Converters.Narrow_to_Wide_Wide.Converter with private;
 
+	overriding function In_Initial_State (State : Converter) return Boolean;
+
 	overriding procedure Reset (State : in out Converter);
 
 	overriding procedure Process (

source/library/encodings-unicode-utf_8-from_utf_32.adb

@@ -1,5 +1,8 @@
 package body Encodings.Unicode.UTF_8.From_UTF_32 is
 
+	overriding function In_Initial_State (State : Converter) return Boolean
+	is (State.L = 0);
+
 	procedure Reset (State : in out Converter) is
 	begin
 		State.L := 0;

source/library/encodings-unicode-utf_8-from_utf_32.ads

@@ -6,6 +6,8 @@ package Encodings.Unicode.UTF_8.From_UTF_32 is
 
 	type Converter is new Converters.Wide_Wide_to_Narrow.Converter with private;
 
+	overriding function In_Initial_State (State : Converter) return Boolean;
+
 	overriding procedure Reset (State : in out Converter);
 
 	overriding procedure Process (