CVS difference for ais/ai-00132.txt
--- ais/ai-00132.txt 1998/09/30 23:25:12 1.2
+++ ais/ai-00132.txt 1999/07/29 00:51:02 1.3
@@ -1,5 +1,6 @@
-!standard A.13 (13) 98-06-12 AI95-00132/03
+!standard A.13 (13) 99-07-28 AI95-00132/04
!class binding interpretation 96-09-05
+!status Corrigendum 2000 99-07-28
!status WG9 approved 98-06-12
!status ARG Approved 11-0-1 97-11-14
!status ARG Approved (subject to letter ballot) 10-0-1 96-10-07
@@ -9,12 +10,12 @@
!subject Exception Raised at End of Stream
If the default version of T'Read (for some type T) is used to read from
a stream, then if end of stream is encountered, End_Error is raised.
Suppose one gets a stream from the Ada.Text_IO.Streams.Stream function.
(The same question applies to the Wide_Text_IO version, and also to
@@ -24,14 +25,16 @@
one tries to get an item using the default version of T'Read, for some
type T? Is Data_Error or End_Error raised? Can the result be abnormal?
13.13.1(8) admits to the notion of "end of stream" for stream types:
The Read operation transfers Item'Length stream elements from the
@@ -125,8 +128,31 @@
if not End_Of_File(An_Input_File) then
+In the default implementation of Read and Input for a composite type,
+for each scalar component that is a discriminant or whose
+@fa<component_declaration> includes a @fa<default_expression>, a check is
+made that the value
+returned by Read for the component belongs to its subtype. Constraint_Error
+is raised if this check fails. For other scalar components, no check is
+made. For each component that is of an access type, if the implementation
+can detect that the value returned by Read for the component is not a value
+of its subtype, Constraint_Error is raised. If the value is not a value of
+its subtype and this error is not detected, the component has an abnormal
+value, and erroneous execution can result (see 13.9.1).
+In the default implementation of Read and Input for a type, End_Error
+is raised if the end of the stream is reached before completing
+to read a value of the type.
+Create a C-Test to test this using Ada.Text_IO.Streams.
!subject Exception raised at end of text stream
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