PROPOSAL: checked exception handling enhancement

[rssh at gradsoft.com.ua]

 May be extend coin-project to include April 1-st ?
  //in wait for proposals about adding plain C preprocessor ;)




> AUTHOR(S):
>
> Eugene Ray
>
> OVERVIEW
>
> FEATURE SUMMARY:
>
> A new class-level modifier keyword, "wtf", is added to the language,
> eliminating the need to explicitly handle every checked exception in the
> class.
>
> MAJOR ADVANTAGE:
>
> Increases readability of code.
>
> MAJOR BENEFIT:
>
> The absence of this feature has resulted in many people writing copious
> quantities of do-nothing catch blocks.═ Also reserving "wtf" as a keyword
> encourages good variable naming practice by forbidding programmers from
> naming identifiers "wtf".
>
> MAJOR DISADVANTAGE:
>
> Many people will no longer write do-nothing catch blocks, freeing up
> programmer time.
>
> ALTERNATIVES:
>
> Continue writing do-nothing catch blocks.
>
> EXAMPLES
>
> SIMPLE EXAMPLE:
>
> In the class shown here, no catch blocks are necessary due to the "wtf"
> modifier at the beginning of the class.
>
>
> public wtf class Amazing {
>
> ══ ═public void readFile (String f) {
> ══ ═══ ═BufferedReader in = new BufferedReader (new FileReader (in));
> ══ ═══ ═String i_should_really_have_used_nio = in.readLine ();
> ══ ═══ ═String there_might_only_be_one_line_but_i_don_t_care = in.readLine
> ();
> ═══════════════ in.close ();
> ═══════════════ String no_exception_just_die = in.readLine ();
> ══ ═}
>
> }
>
>
> Currently, this would be written as:
>
> public wtf class Amazing {
>
> ══ ═public void readFile (String f) {
> ══ ═══ ═try {
> ══ ═══ ═══ ═BufferedReader in = new BufferedReader (new FileReader (in));
> ══ ═══ ═══ ═String i_should_really_have_used_nio = in.readLine ();
> ══ ═══ ═══ ═String there_might_only_be_one_line_but_i_don_t_care =
> in.readLine ();
> ══ ════════════════ in.close ();
> ══ ════════════════ String no_exception_just_die = in.readLine ();
> ══ ═══ ═}
> ══ ═══ ═catch (Exception e) {
> ══ ═══ ═}
> ══ ═}
>
> }
>
>
> ADVANCED EXAMPLE:
>
> Optionally, class-wide error handling is possible via declaring a static
> "wtf" method, which will automatically be called anytime an exception is
> thrown in a wtf class.
>
> public wtf class Amazing {
>
> ══ ═public void readFile (String f) {
> ══ ═══ ═BufferedReader in = new BufferedReader (new FileReader (in));
> ══ ═══ ═String i_should_really_have_used_nio = in.readLine ();
> ══ ═══ ═String there_might_only_be_one_line_but_i_don_t_care = in.readLine
> ();
> ═══════════════ in.close ();
> ═══════════════ String no_exception_just_die = in.readLine ();
> ══ ═}
>
> ══ ═public void writeFile (String f) {
> ══ ═══ ═FileOutputStream out = new FileOutputStream ("*.*");
> ══ ═══ ═out.write (new byte [90090]);
> ══ ═══ ═out.close ();
> ══ ═}
>
> ══ ═public static void wtf (Throwable e, Object instance) {
> ══ ═══ ═System.out.println ("You sure screwed up something, man");
> ══ ═}
>
> }
>
>
> DETAILS
>
> SPECIFICATION:
>
> A new keyword, "wtf", is added to the language.═ This is to be used as a
> modifier for a class declaration and indicates that any checked exception
> thrown within the body of any method in the class is to be automatically
> caught and handled in one of two ways.═ If the class declares a public
> static method named "wtf" which takes in exactly one Throwable and one
> Object parameter, this method will be called every time a checked
> exception occurs with the exception as the Throwable parameter, and the
> instance of the class on which the method was called as the Object
> parameter (or null, if the exception occurs in a static method.)═ If no
> such method is found, no error handling code of any kind is invoked and
> the exception simply vanishes into the aether.═ The method in which the
> exception occurs will immediately return.═ If the method returns an object
> type, it will return null.═ If the method returns a numeric type, it will
> return the minimum value of
>  the appropriate type, and if the method returns a boolean, it will return
> false.
>
> The "wtf" keyword is not context-sensitive; it is simply illegal to use it
> anywhere other than as described, and "wtf" is no longer a valid
> identifier name.
>
> COMPILATION:
>
> This feature will be implemented via a desugaring step by generating catch
> blocks in each instance method as follows:
>
> public int someInstanceMethod () {
> ══ ═// do something
> ══ ═return 42;
> }
>
> becomes:
>
> public int someInstanceMethod () {
> ══ ═try {
> ══ ═══ ═// do something
> ══ ═══ ═return 42;
> ══ ═}
> ══ ═catch (Exception e) {
> ══ ═══ ═wtf (e, this);
> ══ ═══ ═return Integer.MIN_VALUE;
> ══ ═}
> }
>
> and, for static methods:
>
> public static List <String> writeBoringNovelConsistingEntirelyOfPronouns
> () {
> ══ ═List <String> list = new ArrayList <String> ();
> ══ ═// do something;
> ══ ═return list;
> }
>
> becomes:
>
> public static List <String> writeBoringNovelConsistingEntirelyOfPronouns
> () {
> ══ ═try {
> ══ ═══ ═List <String> list = new ArrayList <String> ();
> ══ ═══ ═// do something;
> ══ ═══ ═return list;
> ══ ═}
> ══ ═catch (Exception e) {
> ══ ═══ ═wtf (e, null);
> ══ ═══ ═return null;
> ══ ═}
> }
>
>
> If no public static void wtf (Throwable, Object) method is defined, an
> empty one will be generated as follows:
>
> public static void wtf (Throwable e, Object instance) {
> }
>
> TESTING
>
> Testing can be accomplished by taking an incredibly complex piece of
> existing software,systemically removing all exception-handling code, and
> placing the wtf keyword in all class definitions.═ If the resulting
> application fails in difficult-to-diagnose ways for no discernable reason
> and with no error messages, the wtf keyword has been implemented
> successfully.
>
> LIBRARY SUPPORT:
>
> Entirely unnecessary.
>
> REFLECTIVE APIS:
>
> Entirely unnecessary.
>
> OTHER CHANGES:
>
> Entirely unnecessary.
>
> MIGRATION:
>
> See "TESTING" section above, and hire five additional programmers to
> implement.
>
> COMPATIBILITY
>
> BREAKING CHANGES:
>
> Programs that currently use "wtf" as an identifier will have to be
> altered, as "wtf" will no longer be a legal identifier name.═ The authors
> of such code should be sternly reprimanded if this sort of thing is
> discovered.
>
> REFERENCES
>
> EXISTING BUGS
>
> None, but I will gladly file one if there is sufficient interest.
>
> URL FOR PROTOTYPE (optional):
>
> None yet, although "vi" can be adapted to perform the desugaring step.
>
>
>
>
>
>