Change specification of @proxy to be compatible with implemementation.

docs/language/dartLangSpec.tex

 \documentclass{article}
 \usepackage{epsfig}
 \usepackage{dart}
 \usepackage{bnf}
 \usepackage{hyperref}
 \newcommand{\code}[1]{{\sf #1}}
 \title{Dart Programming Language  Specification \\
-{\large Version 1.0}}
+{\large Version 1.01}}
 \author{The Dart Team}
 \begin{document}
 \maketitle
 
 \tableofcontents
 
 
 \newpage
 
 \pagestyle{myheadings}
@@ skipping 1537 matching lines @@
 \item It is a static warning a concrete class has an abstract member (declared or inherited).
 \item It is a static warning and a dynamic error to call a non-factory constructor of an abstract class  (\ref{new}). 
 \item If a class defines an instance member named $m$, and any of its superinterfaces have a  member named $m$, the interface of the class overrides $m$.
 \item  An interface inherits all  members of its superinterfaces that are not overridden and not members of multiple superinterfaces.
 \item  If multiple superinterfaces of an interface define a member with the same name $m$, then at most one member is inherited. That member (if it exists) is the one whose type is a subtype of all the others. If there is no such member, then:
 \begin{itemize}
   \item  A static warning is given.
   \item  If possible the interface gets a member named $m$ that has the minimum number of required parameters among all the members in the superinterfaces, the maximal number of    positionals, and the superset of named parameters.  The types of these are all \DYNAMIC{}. If this is impossible then no member $m$ appears in the interface.
   \end{itemize}  (\ref{interfaceInheritanceAndOverriding})
 \item  Rule \ref{typeSigAssignable} applies to interfaces as well as classes  (\ref{interfaceInheritanceAndOverriding}).
-\item  It is a static warning if a concrete class does not have an implementation for a  method in any of its superinterfaces  unless it declares  its own \cd{noSuchMethod} method (\ref{superinterfaces}) or is annotated with \cd{@proxy}.
+\item  It is a static warning if a concrete class does not have an implementation for a  method in any of its superinterfaces  unless it declares  its own \cd{noSuchMethod} method (\ref{superinterfaces}). 
 \item The identifier of a named constructor cannot be the same as the name of a member declared (as opposed to inherited) in the same class (\ref{constructors}).
 \end{enumerate}
 }
 
 
 %Can we have abstract getters and setters?
 
 \subsection{Superinterfaces}
 \label{superinterfaces}
 % what about rules about classes that fail to implement their interfaces?
 
 A class has a set of direct superinterfaces. This set includes the interface of its superclass and the interfaces specified in the the \IMPLEMENTS{}  clause of the class.
 % and any superinterfaces specified by interface injection (\ref{interfaceInjection}).  \Q{The latter needs to be worded carefully - when do interface injection clauses execute and in what scope?}
 
 \begin{grammar}
 {\bf interfaces:}
       \IMPLEMENTS{} typeList
     .
 \end{grammar}
 
 It is a compile-time error if  the \IMPLEMENTS{}  clause of a class $C$ specifies a type variable as a superinterface. It is a compile-time error if  the  \IMPLEMENTS{} clause of a class $C$ specifies  a malformed type as a superinterface  It is a compile-time error if the \IMPLEMENTS{} clause of a class $C$ specifies type \DYNAMIC{} as a superinterface. It is a compile-time error if  the  \IMPLEMENTS{} clause of a class $C$ specifies  a type $T$ as a superinterface more than once.
 It is a compile-time error if the superclass of a class $C$ is specified as a superinterface of $C$.
 
 \rationale{
 One might argue that it is harmless to repeat a type in the superinterface list, so why make it an error? The issue is not so much that the situation described in program source is erroneous, but that it is pointless. As such, it is an indication that the programmer may very well have meant to say something else - and that is a mistake that should be called to her or his attention.  Nevertheless, we could simply issue a warning; and perhaps we should and will. That said, problems like these are local and easily corrected on the spot, so we feel justified in taking a harder line. 
 }
 
 It is a compile-time error if the interface of a class $C$ is a superinterface of itself.
 
-Let $C$ be a concrete class that does not declare its own \code{noSuchMethod()} method and is not annotated with a metadata declaration of the form \cd{@proxy}, where \cd{proxy} is declared in \cd{dart:core}.
+Let $C$ be a concrete class that does not declare its own \code{noSuchMethod()} method.
 It is a static warning if the implicit interface of  $C$ includes an instance member $m$ of type $F$ and $C$ does not declare or inherit a corresponding instance member $m$ of type $F'$ such that $F' <: F$. 
 
 \commentary{A class does not inherit members from its superinterfaces. However, its implicit interface does.
 }
 
 
 \rationale {
 We choose to issue these warnings only for concrete classes; an abstract class might legitimately be designed with the expectation that concrete subclasses will implement part of  the interface.
 We also disable these warnings if a \code{noSuchMethod()} declaration is present. In such cases, the supported interface is going to be implemented via \code{noSuchMethod()} and no actual declarations of the implemented interface's members are needed. This allows proxy classes for specific types to be implemented without provoking type warnings.
 
-In addition, it may be useful to suppress these warnings if \code{noSuchMethod} is inherited, However, this may suppress meaningful warnings and so we choose not to do so by default. Instead, a special annotation is defined in \cd{dart:core} for this purpose.
+In addition, it may be useful to suppress these warnings if \code{noSuchMethod} is inherited, However, this may suppress meaningful warnings and so we choose not to do so. If one does want to suppress the warnings in a subclass, one can define a simple implementation of \code{noSuchMethod} in the subclass:
 }
 
+\begin{dartCode}
+noSuchMethod(inv) =$>$ \SUPER.noSuchMethod(inv);
+\end{dartCode}
+
 It is a static warning if the implicit interface of  a class $C$ includes an instance member $m$ of type $F$ and $C$ declares or inherits a corresponding instance member $m$ of type $F'$ if  $F'$ is not a subtype of $F$. 
 
 \rationale{
 However, if a class does explicitly declare a member that conflicts with its superinterface, this always yields a static warning.
 
 }
 %It is a static warning if an imported superinterface of a class $C$ declares private members.
 
 % Should we ignore unimplemented private members? 
 
@@ skipping 1547 matching lines @@
 \item  \code{im.isMethod} evaluates to \code{\TRUE{}}.
 \item  \code{im.memberName} evaluates to \code{'m'}.
 \item \code{im.positionalArguments} evaluates to an immutable list with the same values as  \code{[$o_1, \ldots, o_n$]}.
 \item \code{im.namedArguments} evaluates to an immutable map with the same keys and values as \code{\{$x_{n+1}: o_{n+1}, \ldots, x_{n+k} : o_{n+k}$\}}.
 \end{itemize}
 
 Then the method \code{noSuchMethod()} is looked up in $o$ and invoked with argument $im$, and the result of this invocation is the result of evaluating $i$.
 
 \commentary{Notice that the wording carefully avoids re-evaluating the receiver $o$ and the arguments $a_i$. }
 
-Let $T$ be the  static type of $o$. It is a static type warning if $T$ does not have an accessible  (\ref{privacy}) instance member named $m$.   If $T.m$ exists, it  is a static type warning if the type $F$ of $T.m$ may not be assigned to a function type. If $T.m$ does not exist, or if $F$ is not a function type, the static type of $i$ is \DYNAMIC{}; otherwise the static type of $i$ is the declared return type of  $F$.  
+Let $T$ be the  static type of $o$. It is a static type warning if $T$ does not have an accessible  (\ref{privacy}) instance member named $m$ unless $T$ or a superinterface of $T$ is annotated with an annotation denoting a constant identical to the constant \code{@proxy} defined in \code{dart:core}.   If $T.m$ exists, it  is a static type warning if the type $F$ of $T.m$ may not be assigned to a function type. If $T.m$ does not exist, or if $F$ is not a function type, the static type of $i$ is \DYNAMIC{}; otherwise the static type of $i$ is the declared return type of  $F$.  
 %\item Let $T_i$ be the static type of $a_i, i \in 1 .. n+k$. It is a static warning if $F$ is not a supertype of  $(T_1, \ldots, T_n, [T_{n+1}$ $x_{n+1}, \ldots, T_{n+k}$ $x_{n+k}]) \to \bot$.
 %\end{itemize}
 
 
 %\subsubsection{This Invocation}
 % Maybe this has no significance the way the language is set up?
 
 
 \subsubsection{Cascaded Invocations}
 \label{cascadedInvocations}
@@ skipping 75 matching lines @@
 \begin{itemize}
 \item  \code{im.isMethod} evaluates to \code{\TRUE{}}.
 \item  \code{im.memberName} evaluates to \code{'m'}.
 \item \code{im.positionalArguments} evaluates to an immutable list with the same  values as  \code{[$o_1, \ldots, o_n$]}.
 \item \code{im.namedArguments} evaluates to an immutable map with the same keys and values as \code{\{$x_{n+1}: o_{n+1}, \ldots, x_{n+k} : o_{n+k}$\}}.
 \end{itemize}
 Then the method \code{noSuchMethod()} is looked up in $S$ and invoked on \THIS{} with argument $im$, and the result of this invocation is the result of evaluating $i$.
 
 It is a compile-time error if a super method invocation occurs in a top-level function or variable initializer, in an instance variable initializer or initializer list, in class \code{Object}, in a factory constructor or in a static method or variable initializer.
 
-It is a static type warning if $S$ does not have an accessible (\ref{privacy}) instance member named $m$. If $S.m$ exists, it  is a static type warning if the type $F$ of $S.m$ may not be assigned to a function type. If $S.m$ does not exist, or if $F$ is not a function type, the static type of $i$ is \DYNAMIC{}; otherwise the static type of $i$ is the declared return type of  $F$.  
+It is a static type warning if $S$ does not have an accessible (\ref{privacy}) instance member named $m$ unless $S$ or a superinterface of $S$ is annotated with an annotation denoting a constant identical to the constant \code{@proxy} defined in \code{dart:core}. If $S.m$ exists, it  is a static type warning if the type $F$ of $S.m$ may not be assigned to a function type. If $S.m$ does not exist, or if $F$ is not a function type, the static type of $i$ is \DYNAMIC{}; otherwise the static type of $i$ is the declared return type of  $F$.  
 %\item Let $T_i$ be the static type of $a_i, i \in 1 .. n+k$. It is a static warning if $F$ is not a supertype of  $(T_1, \ldots, t_n, [T_{n+1}$ $x_{n+1}, \ldots, T_{n+k}$ $x_{n+k}]) \to \bot$.
 %\end{itemize}
 
 
 
 \subsubsection{Sending Messages}
 
 \label{sendingMessages}
 
 Messages are the sole means of communication among isolates. Messages are sent by invoking specific  methods in the Dart libraries; there is no specific syntax for sending a message. 
@@ skipping 26 matching lines @@
 
 If the getter lookup has failed, then a new instance $im$  of the predefined class  \code{Invocation}  is created, such that :
 \begin{itemize}
 \item  \code{im.isGetter} evaluates to \code{\TRUE{}}.
 \item  \code{im.memberName} evaluates to \code{'m'}.
 \item \code{im.positionalArguments} evaluates to the value of \code{\CONST{} []}.
 \item \code{im.namedArguments} evaluates to the value of \code{\CONST{} \{\}}.
 \end{itemize}
 Then the method \code{noSuchMethod()} is looked up in $o$ and invoked  with argument $im$, and the result of this invocation is the result of evaluating $i$.
 
-Let $T$ be the  static type of $e$. It is a static type warning if $T$ does not have a getter named $m$. The static type of $i$ is the declared return type of $T.m$, if $T.m$ exists; otherwise the static type of $i$  is  \DYNAMIC{}. 
+Let $T$ be the  static type of $e$. It is a static type warning if $T$ does not have a getter named $m$ unless $T$ or a superinterface of $T$ is annotated with an annotation denoting a constant identical to the constant \code{@proxy} defined in \code{dart:core}. The static type of $i$ is the declared return type of $T.m$, if $T.m$ exists; otherwise the static type of $i$  is  \DYNAMIC{}. 
 
 Evaluation of a getter invocation $i$ of the form $C.m$ proceeds as follows:
 
 If  there is no class $C$ in the enclosing lexical scope of $i$, or if  $C$ does not declare, implicitly or explicitly, a getter named $m$, then a \code{NoSuchMethodError} is thrown. 
 Otherwise, the getter function $C.m$ is invoked. The value of $i$ is the result returned by the call to the getter function. 
 
 It is a static warning  if there is no class $C$ in the enclosing lexical scope of $i$, or if  $C$ does not declare, implicitly or explicitly, a getter named $m$. The static type of $i$ is the declared return type of $C.m$ if it exists or \DYNAMIC{} otherwise. 
 
 Evaluation of a top-level getter invocation $i$ of the form $m$, where $m$ is an identifier, proceeds as follows:
 
@@ skipping 85 matching lines @@
 \item  \code{im.isSetter} evaluates to \code{\TRUE{}}.
 \item  \code{im.memberName} evaluates to \code{'v='}.
 \item \code{im.positionalArguments} evaluates to an immutable list with the same values as \code{[$o_2$]}.
 \item \code{im.namedArguments} evaluates to the value of \code{\CONST{} \{\}}.
 \end{itemize}
 
 Then the method \code{noSuchMethod()} is looked up in $o_1$ and invoked  with argument $im$. The value of the assignment expression is $o_2$ irrespective of whether setter lookup has failed or succeeded.
 
 In checked mode, it is a dynamic type error if $o_2$ is not \NULL{} and the interface of the class of $o_2$ is not a subtype of the actual type of $e_1.v$.
 
-Let $T$ be the static type of $e_1$. It is a static type warning if $T$ does not have an accessible instance setter named $v=$. It is a static type warning if the static type of $e_2$ may not be assigned to $T$.   The static type of the expression $e_1v$ \code{=} $e_2$ is the static type of $e_2$.
+Let $T$ be the static type of $e_1$. It is a static type warning if $T$ does not have an accessible instance setter named $v=$ unless $T$ or a superinterface of $T$ is annotated with an annotation denoting a constant identical to the constant \code{@proxy} defined in \code{dart:core}. It is a static type warning if the static type of $e_2$ may not be assigned to $T$.   The static type of the expression $e_1v$ \code{=} $e_2$ is the static type of $e_2$.
 
 Evaluation of an assignment of the form $e_1[e_2]$ \code{=} $e_3$ is equivalent to the evaluation of the expression \code{(a, i, e)\{a.[]=(i, e); \RETURN{} e; \} ($e_1, e_2, e_3$)}.  The static type of the expression $e_1[e_2]$ \code{=} $e_3$ is the static type of $e_3$.
 
 % Should we add: It is a dynamic error if $e_1$ evaluates to an  constant list or map.
 
 It is as static warning if an assignment of the form $v = e$ occurs inside a top level or static function (be it function, method, getter, or setter) or variable initializer and there is neither a local variable declaration with name $v$  nor setter declaration with name $v=$ in the lexical scope enclosing the assignment.
 
 
 
 \subsubsection{Compound Assignment}
@@ skipping 270 matching lines @@
 The static type of an multiplicative expression is usually determined by the signature given in the declaration of the operator used. However, invocations of the operators \cd{*}, \cd{\%}  and \cd{\~{}/} of class \cd{int} are treated specially by the typechecker. The static type of an expression $e_1 * e_2$ where $e_1$ has static type \cd{int} is \cd{int} if the static type of $e_2$ is \cd{int}, and \cd{double} if the static type of $e_2$ is \cd{double}. The static type of an expression $e_1 \% e_2$ where $e_1$ has static type \cd{int} is \cd{int} if the static type of $e_2$ is \cd{int}, and \cd{double} if the static type of $e_2$ is \cd{double}.  The static type of an expression \cd{$e_1$ \~{}/ $e_2$} where $e_1$ has static type \cd{int} is \cd{int} if the static type of $e_2$ is \cd{int}.
  
 \subsection{ Unary Expressions}
 \label{unaryExpressions}
 
 Unary expressions invoke unary operators on objects.
 
 \begin{grammar}
 {\bf unaryExpression:}prefixOperator unaryExpression;
       postfixExpression;
-      prefixOperator \SUPER{};
+      (minusOperator $|$ tildeOperator) \SUPER{};
       incrementOperator assignableExpression
     .
  
- {\bf prefixOperator:}`-';
-      unaryOperator
+ {\bf prefixOperator:}minusOperator;
+      negationOperator;
+      tildeOperator
     .
        
-    {\bf unaryOperator:}`!' ;
-      `\~{}'
+       
+  {\bf minusOperator:}`-';  .
+
+
+    {\bf negationOperator:}`!' ;
+      .
+      
+    {\bf tildeOperator:}  `\~{}'
     .
     
     
 \end{grammar}
 
-A {\em unary expression} is either aa postfix expression  (\ref{postfixExpressions}), an invocation of a prefix operator on an expression or an invocation of a unary operator on either \SUPER{} or an expression $e$.
+A {\em unary expression} is either a postfix expression  (\ref{postfixExpressions}), an invocation of a prefix operator on an expression or an invocation of a unary operator on either \SUPER{} or an expression $e$.
 
 The expression $!e$ is equivalent to the expression $e? \FALSE{} :\TRUE{}$. 
 
 Evaluation of an expression of the form \code{++$e$} is equivalent to \code{$e$ += 1}.  Evaluation of an expression of the form \code{-{}-$e$} is equivalent to \code{$e$ -= 1}. 
 
 %The expression $-e$ is equivalent to the method invocation \code{$e$.-()}.  The expression \code{-\SUPER{}} is equivalent  to the method invocation \code{\SUPER{}.-()}.
 
 An expression of the form \code{$op$ $e$} is equivalent to the method invocation \code{$e.op()$}. An expression of the form \code{$op$ \SUPER{}} is equivalent to the method invocation \code{\SUPER{}.$op()$}.
 
 
@@ skipping 839 matching lines @@
 %\commentary{The active stack trace contains the frames between the exception handling code and the original point when an exception is thrown, not where it was rethrown.}
 %\end{enumerate}
 
  \commentary{
 This implies that no synthetic function activations may be added to the trace, nor may any source level activations be omitted. 
 This means, for example, that any inlining of functions done as an optimization must not be visible in the trace. Similarly, any synthetic routines used by the implementation must not appear in the trace.
 
 Nothing is said about how any native function calls may be represented in the trace.
  }
  
+\commentary{
+Note that we say nothing about the identity of the stack trace, or what notion of equality is defined for stack traces.
+}
  
- For each such function activation, the active stack trace includes the name of the function, the bindings of all its formal parameters, local variables and \THIS{}, and the position at which the function was executing.
+% Sadly, the info below cannot be computed efficiently. It would need to be computed at the throw point, since at latte points it might be destroyed. Native code in calling frames executes relative to the stack pointer, which therefore needs to be reset as each frame is unwound.  This means that the
+% OS kernel can dispose of this stack memory - it is not reliably preserved. And such code must execute if only to test if the exception should be caught or sent onward.
+
+% For each such function activation, the active stack trace includes the name of the function, the bindings of all its formal parameters, local variables and \THIS{}, and the position at which the function was executing.
  
  % Is this controversial? We were thinking of viewing the trace as a List<Invocation>,
  % but that won't capture the receiver or the locals. More generally, we need a standard interface that describes these traces, so one can type the stack trace variable in the catch.
  
  \commentary{The term position should not be interpreted as a line number, but rather as a precise position - the exact character index of the  expression that raised  the exception. }
  
  % A position can be represented via a Token. If we make that part of the core reflection facility, we can state this here.
  
  \rationale{The definition below is an attempt to characterize exception handling without resorting to a normal/abrupt completion formulation. It has the advantage that one need not specify abrupt completion behavior for every compound statement.  On the other hand, it is new and different and needs more thought.
 }
@@ skipping 420 matching lines @@
 A library $L$ exports a namespace (\ref{scoping}), meaning that the declarations in the namespace are made available to other libraries if they choose to import $L$ (\ref{imports}).  The namespace that $L$ exports is known as its {\em exported namespace}.
 
 \begin{grammar}
 {\bf libraryExport:}
    metadata \EXPORT{}  uri  combinator* `{\escapegrammar ;}'
     .
  \end{grammar}
  
  An export specifies a URI $x$ where the declaration of an exported library is to be found.  It is a compile-time error if  the specified URI does not refer to a library declaration.  
 
-We say that a name {\em is exported by a library} (or equivalently, that a library {\em exports a name}) if the name is in the library`s exported namespace. We say that a declaration {\em is exported by a library} (or equivalently, that a library {\em exports a declaration}) if the declaration is in the library`s exported namespace.
+We say that a name {\em is exported by a library} (or equivalently, that a library {\em exports a name}) if the name is in the library's exported namespace. We say that a declaration {\em is exported by a library} (or equivalently, that a library {\em exports a declaration}) if the declaration is in the library`s exported namespace.
 
 A library always exports all names and all declarations in its public namespace. In addition, a library may choose to re-export additional libraries via {\em export directives}, often referred to simply as {\em exports}.
 
 Let $E$ be an export directive that refers to a URI via the string $s_1$. Evaluation of $E$  proceeds as follows:
 
 First,
 
  \begin{itemize}
  \item
 If  the URI that is the value of $s_1$ has not yet been accessed by an import or export directive  in the current isolate then the contents of the URI  are compiled to yield a library $B$.
@@ skipping 19 matching lines @@
 \item The export from \code{dart:} is implicitly extended by a \code{\HIDE{} $N$} clause.
 \item A static warning is issued.
 \end{itemize}
 
 \rationale{
 See the discussion in section \ref{imports} for the reasoning behind this rule.
 }
 
 We say that $L$ {\em re-exports library } $B$, and also that $L$ {\em re-exports namespace } $NS_n$. When no confusion can arise, we may simply state that $L$ {\em re-exports }$B$, or that $L$ {\em re-exports }$NS_n$.
 
-It is a compile-time error if a name $N$ is re-exported by a library $L$ and $N$ is  introduced into the export namespace of $L$ by more than one export, unless each all exports refer to same declaration for the name $N$.  It is a static warning to export two different libraries with the same name.
+It is a compile-time error if a name $N$ is re-exported by a library $L$ and $N$ is  introduced into the export namespace of $L$ by more than one export, unless all  exports refer to same declaration for the name $N$.  It is a static warning to export two different libraries with the same name.
 
 
 
 \subsection{Parts}
 \label{parts}
 
 A library may be divided into {\em parts}, each of which can be stored in a separate location. A library identifies its parts by listing them via \PART{} directives. 
 
 A {\em part directive} specifies a URI where a Dart compilation unit that should be incorporated into the current library may be found.
 
@@ skipping 671 matching lines @@
 
 Operator precedence is given implicitly by the grammar.
 
 \commentary{The following non-normative table may be helpful
 \newline
 
 \begin{tabular}{| r | r | r | r |}
 \hline
 Description &  Operator & Associativity & Precedence \\ 
 \hline
-Unary postfix &  ., ?id, e++, e--, e1[e2], e1() , () & None & 15 \\
+Unary postfix &  ., e++, e--, e1[e2], e1() , () & None & 15 \\
 \hline
 Unary prefix & -e, !e, \~{}e, ++e, --e & None & 14\\
 \hline
 Multiplicative & *, /, \~/,  \%  & Left & 13\\
 \hline
 Additive & +, - & Left & 12\\
 \hline 
 Shift &  $<<$, $>>$&  Left & 11\\
 \hline
 Bitwise AND & \& & Left & 10\\
@@ skipping 30 matching lines @@
 \item The names of compile time constant variables never use lower case letters. If they consist of multiple words, those words are separated by underscores. Examples: PI,  I\_AM\_A\_CONSTANT.
 \item The names of functions (including getters, setters, methods and local or library functions) and non-constant variables begin with a lowercase letter. If the name consists of multiple words, each  word (except the first) begins with an uppercase letter.  No other uppercase letters are used. Examples: camlCase, dart4TheWorld
 \item The names of types (including classes and type aliases) begin with an upper case letter.  If the name consists of multiple words, each  word  begins with an uppercase letter.  No other uppercase letters are used. Examples: CamlCase, Dart4TheWorld.
 \item The names of type variables are short (preferably single letter). Examples: T, S, K, V , E.
 \item The names of libraries or library prefixes never use upper case letters. If they consist of multiple words, those words are separated by underscores. Example: my\_favorite\_library.
 \end{itemize}
 }
 
 
 \end{document}