CVS difference for arm/source/04a.mss

Differences between 1.84 and version 1.85
Log of other versions for file arm/source/04a.mss

--- arm/source/04a.mss	2007/02/06 04:48:40	1.84
+++ arm/source/04a.mss	2007/02/18 03:22:24	1.85
@@ -1,10 +1,10 @@
 @Part(04, Root="ada.mss")
-@Comment{$Date: 2007/02/06 04:48:40 $}
+@Comment{$Date: 2007/02/18 03:22:24 $}
 @LabeledSection{Names and Expressions}
 @Comment{$Source: e:\\cvsroot/ARM/Source/04a.mss,v $}
-@Comment{$Revision: 1.84 $}
+@Comment{$Revision: 1.85 $}
 @Redundant[The rules applicable to the different forms of @nt<name> and
@@ -53,10 +53,10 @@
 @Redundant[Certain forms of @nt<name> (@nt<indexed_component>s,
 @nt<selected_component>s, @nt<slice>s, and
 include a @nt<prefix> that is either itself a @nt<name> that denotes
 some related entity, or an @nt<implicit_dereference> of an access
 value that designates some related entity.]
@@ -1171,6 +1171,14 @@
 See @RefSec{The Context of Overload Resolution}
 for the meaning of @lquotes@;shall be a single ... type.@rquotes@;
+@ChgAdded{Version=[3],Text=[There are additional rules for each kind of
+aggregate. These aggregate rules are additive; a legal expression needs to
+satisfy all of the applicable rules. That means the rule given here must be
+satisfied even when it is syntactally possible to tell which specific kind of
+aggregate is being used.]}
@@ -1454,15 +1462,24 @@
 then it shall be a descendant of a record type, through one
 or more record extensions (and no private extensions).
-If there are no components needed in a given
+@Chg{Version=[3],New=[The reserved words @key[null record] may appear only if],
+Old=[If]} there are no components needed in a given
 then the reserved words @key(null record) shall appear rather
-than a list of @nt<record_@!component_@!association>s.
+than a list of @nt<record_@!component_@!association>s]}.
   For example, "(@key(null record))" is a @nt<record_aggregate>
   for a null record type. Similarly, "(T'(A) @key(with null record))" is
   an @nt<extension_aggregate> for a type defined as a null
   record extension of T.
+@ChgAdded{Version=[3],Text=[If no components are needed and @key[null record]
+  is not used, the @nt{record_@!component_@!association} must necessarily be
+  @key[others] => <>, as that is the only
+  @nt{record_@!component_@!association} that does not require an associated
+  component.]}
@@ -1579,6 +1596,16 @@
 The @nt<expression> of a @nt{record_component_association}
 is evaluated (and converted) once for each associated component.
+@ChgAdded{Version=[3],Text=[We don't need similar language for <>,
+as we're considering the value of <> for each individual component.
+Each component has its own default expression or its own
+default initialization (they can be different for each component;
+the components even could have different types), and each one
+has to be evaluated. So there is no need to repeat that.]}
@@ -1663,6 +1690,13 @@
   @ChgAdded{Version=[2],Text=[Limited @nt{record_aggregate}s are allowed (since
   all kinds of aggregates can now be limited, see @RefSecNum{Aggregates}).]}
+  @ChgRef{Version=[3],Kind=[AddedNormal],ARef=[AI05-0016-1]}
+  @ChgAdded{Version=[3],Text=[@b<Corrigendum 2:> Fixed the wording so that
+  @key[others] => <> can be used in place of @key[null record].
+  This is needed to avoid a generic contract issue for generic bodies:
+  we do not want to have to assume the worst to disallow others => <>
+  if the record type @i{might} be a null record.]}
@@ -1715,6 +1749,17 @@
 get too complicated, the implementation gets more difficult and
 it becomes harder to produce good error messages.
+@ChgAdded{Version=[3],Text=[This rule is additive with the rule given in
+@RefSecNum{Aggregates}. That means that rule must be satisfied even though it
+is alway syntactally possible to tell that something is an extension aggregate
+rather than another kind of aggregate. Specifically, that means that an
+extension aggregate is ambiguous if the context is overloaded on array and/or
+untagged record types, even though those are never legal contexts for an
+extension aggregate. Thus, this rule acts more like a legality rule than a
+name resolution rule.]}
@@ -2090,6 +2135,16 @@
   Subaggregates are not separately evaluated.
   The conversion of the value of the component expressions
   to the component subtype might raise Constraint_Error.
+@ChgAdded{Version=[3],Text=[We don't need to say that <> is
+  evaluated once for each component, as it means that each component
+  is @i{initialized by default}. That means that the actions defined
+  for default initialization are applied to each component individually.
+  Initializing one component by default and copying
+  that to the others would be an incorrect implementation in general
+  (although it might be OK if the default initialization is known
+  to be constant).]}
@@ -2178,11 +2233,11 @@
 In an @nt<array_aggregate>, positional notation may only be used
 with two or more @nt<expression>s; a single @nt<expression>
 in parentheses is interpreted as a
-@Chg{Version=[2],New=[parenthesized expression],Old=[@ntf{parenthesized_expression}]}.
+@Chg{Version=[3],New=[parenthesized expression],Old=[@ntf{parenthesized_expression}]}.
 A @nt<named_array_aggregate>, such as (1 => X), may be used to specify
 an array with a single component.
@@ -2977,8 +3032,10 @@
   @ChgAdded{Version=[2],Text=[its result type is Boolean;]}
+  @ChgRef{Version=[3],Kind=[Added],ARef=[AI05-0020-1]}
   @ChgAdded{Version=[2],Text=[it is declared immediately within the same
-  declaration list as @i<D>; and]}
+  declaration list as @i<D>@Chg{Version=[3],New=[ or any partial or incomplete
+  view of @i<D>],Old=[]}; and]}
   @ChgAdded{Version=[2],Text=[at least one of its operands is an
@@ -3396,6 +3453,13 @@
 @Chg{Version=[2],New=[Memberships were adjusted to allow interfaces which don't
 cover the tested type, in order to be consistent with type
+@ChgAdded{Version=[3],Text=[@b<Corrigendum 2:> Wording was added to clarify
+that @i{universal_access} "=" does not apply if an appropriate operator is
+declared for a partial or incomplete view of the designated type.
+Otherwise, adding a partial or incomplete view could made some "=" operators
@@ -3706,8 +3770,10 @@
 primitive multiplication operator such that:]}
+  @ChgRef{Version=[3],Kind=[Added],ARef=[AI05-0020-1]}
   @ChgAdded{Version=[2],Text=[it is declared immediately within the same
-  declaration list as the type; and]}
+  declaration list as the type@Chg{Version=[3],New=[ or any partial
+  view thereof],Old=[]}; and]}
   @ChgAdded{Version=[2],Text=[both of its formal parameters are of a
@@ -3903,6 +3969,15 @@
 it causes, since it is unlikely that the user wanted to use predefined
 operators when they had defined user-defined versions.],Old=[]}
+@ChgAdded{Version=[3],Text=[@b<Corrigendum 2:> Wording was added to clarify
+that @i{universal_fixed} "*" and "/" does not apply if an appropriate
+operator is declared for a partial view of the designated type.
+Otherwise, adding a partial view could made some "*" and "/" operators
 @LabeledSubClause{Highest Precedence Operators}

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