Modified:
   doc/trunk/design/syn/S02.pod
   doc/trunk/design/syn/S04.pod
   doc/trunk/design/syn/S06.pod
   doc/trunk/design/syn/S09.pod
   doc/trunk/design/syn/S12.pod

Log:
delete ambiguous use of {...} for hash unpacking, just use sigs for that
  (list unpacking may still be done with [...] for clarity)
simplify parsing of expressions in conditionals to dwim on map/grep blocks
  (you now need to parenthesize only on listops called with 0 args, like caller)
define .pick on enumerable types, e.g. Day.pick
clean out old instances of rand ARG, esp. where used as example of 0-or-1-ary
revamp obsolete usages of exists

Modified: doc/trunk/design/syn/S02.pod
=========================================================================== ===
--- doc/trunk/design/syn/S02.pod        (original)
+++ doc/trunk/design/syn/S02.pod        Tue Oct 14 17:14:18 2008
@@ -12,9 +12,9 @@

   Maintainer: Larry Wall <la...@wall.org>
   Date: 10 Aug 2004
-  Last Modified: 9 Oct 2008
+  Last Modified: 14 Oct 2008
   Number: 2
-  Version: 138
+  Version: 139

 This document summarizes Apocalypse 2, which covers small-scale
 lexical items and typological issues.  (These Synopses also contain
@@ -1096,8 +1096,8 @@

     # Anything assigned to the variable $mitsy must conform
     # to the type Fish and either the Cat or Dog type...
-    my Cat|Dog Fish $mitsy = new Fish but { int rand 2 ?? .does Cat
-                                                       !! .does Dog };
+    my Cat|Dog Fish $mitsy = new Fish but { Bool.pick ?? .does Cat
+                                                      !! .does Dog };

 =head2 Parameter types

Modified: doc/trunk/design/syn/S04.pod
=========================================================================== ===
--- doc/trunk/design/syn/S04.pod        (original)
+++ doc/trunk/design/syn/S04.pod        Tue Oct 14 17:14:18 2008
@@ -12,9 +12,9 @@

   Maintainer: Larry Wall <la...@wall.org>
   Date: 19 Aug 2004
-  Last Modified: 1 Sep 2008
+  Last Modified: 14 Oct 2008
   Number: 4
-  Version: 69
+  Version: 70

 This document summarizes Apocalypse 4, which covers the block and
 statement syntax of Perl.
@@ -1080,11 +1080,11 @@
     }

 parentheses aren't necessary around C<EXPR> because the whitespace
-between C<EXPR> and the block forces the block to be considered a
-block rather than a subscript.  This works for all control structures,
-not just the new ones in Perl 6.  A top-level bare block
-is always considered a statement block if there's space
-before it:
+between C<EXPR> and the block forces the block to be considered a block
+rather than a subscript, provided the block occurs where an infix
+operator would be expected.  This works for all control structures,
+not just the new ones in Perl 6.  A top-level bare block is always
+considered a statement block if there's a term and a space before it:

     if $foo { ... }
     elsif $bar { ... }
@@ -1094,30 +1094,24 @@

 You can still parenthesize the expression argument for old times'
 sake, as long as there's a space between the closing paren and the
-opening brace.  You I<must> parenthesize the expression if there is
-a bare block or pointy block that would be misinterpreted as the statement's
-block.  This is regardless of whether a term or operator is expected where
-the block occurs.  (A block inside brackets, or used as a
-postcircumfix is fine, though.)  Any block with whitespace
-in front of it will be taken as terminating the conditional, even if
-the conditional expression could take another argument.  Therefore
-
-    if rand { say "exists" } { extra() }
-    if rand -> $x { say "exists" } { extra() }
-
-is always parsed as
-
-    if (rand) { say "exists" }; { extra() }
-    if (rand) -> $x { say "exists" }; { extra() }
-
-rather than
-
-    if (rand { say "exists" }) { extra() }
-    if (rand (-> $x { say "exists" })) { extra() }
-
-Apart from that, it is illegal to use a bare closure where an
-operator is expected.  (Remove the whitespace if you wish it to be
-a postcircumfix.)
+opening brace.  (Otherwise it will be parsed as a hash subscript.)
+
+Note that the parser cannot intuit how many arguments a list operator
+is taking, so if you mean 0 arguments, you must parenthesize the
+argument list to force the block to appear after a term:
+
+    if caller {...}    # WRONG, parsed as caller({...})
+    if caller() {...}  # okay
+    if (caller) {...}  # okay
+
+Note that common idioms work as expected though:
+
+    for map { $^a + 1 }, @list { .say }
+
+Unless you are parsing a statement that expects a block argument,
+it is illegal to use a bare closure where an operator is expected
+because it will be considered to be two terms in row.
+(Remove the whitespace if you wish it to be a postcircumfix.)

 Anywhere a term is expected, a block is taken to be a closure definition
 (an anonymous subroutine).  If the closure is empty, or appears to contain

Modified: doc/trunk/design/syn/S06.pod
=========================================================================== ===
--- doc/trunk/design/syn/S06.pod        (original)
+++ doc/trunk/design/syn/S06.pod        Tue Oct 14 17:14:18 2008
@@ -13,9 +13,9 @@

   Maintainer: Larry Wall <la...@wall.org>
   Date: 21 Mar 2003
-  Last Modified: 11 Oct 2008
+  Last Modified: 14 Oct 2008
   Number: 6
-  Version: 95
+  Version: 96

 This document summarizes Apocalypse 6, which covers subroutines and the
@@ -713,10 +713,8 @@
 undefined is not considered to be missing, and hence does not trigger
 the default.  Use C<//=> within the body for that.)

-(Conjectural: Within the body you may also use C<exists> on the
-parameter name to determine whether it was passed.  Maybe this will have to
-be restricted to the C<?> form, unless we're willing to admit that a parameter
-could be simultaneously defined and non-existent.)
+You may check whether an optional parameter was bound to anything
+by calling C<VAR($param).defined>.

 =head2 Named parameters

@@ -1356,39 +1354,9 @@

     sub quicksort (:$reverse, :$inplace, *$pivot, *@data)

-=head2 Unpacking hash parameters
-
-Likewise, a hash argument can be mapped to a hash of parameters, specified
-as named parameters within curlies.  Instead of saying:
-
-    sub register (%guest_data, $room_num) {
-        my $name := delete %guest_data<name>;
-        my $addr := delete %guest_data<addr>;
-        ...
-    }
-
-you can get the same effect with:
-
-    sub register ({:$name, :$addr, *%guest_data}, $room_num) {
-        ...
-    }
-
-Use of the curly form is not allowed where it might be confused with the
-following block's opening curly:
-
-    -> {:$name, :$addr, *%guest_data}, $room_num {  # WRONG
-
-However, as described in the next section, you can always use a
-sub-signature instead:
-
-    -> (:$name, :$addr, *%guest_data), $room_num {  # note ()'s
-
-In fact, the [...] and {...} forms are really just extra documentation
-about what you expect.
-
 =head2 Unpacking tree node parameters

-You can unpack tree nodes in various dwimmy ways by enclosing the bindings
+You can unpack hash values and tree nodes in various dwimmy ways by enclosing the bindings
 of child nodes and attributes in parentheses following the declaration of
 the node itself:

Modified: doc/trunk/design/syn/S09.pod
=========================================================================== ===
--- doc/trunk/design/syn/S09.pod        (original)
+++ doc/trunk/design/syn/S09.pod        Tue Oct 14 17:14:18 2008
@@ -12,9 +12,9 @@

   Maintainer: Larry Wall <la...@wall.org>
   Date: 13 Sep 2004
-  Last Modified: 17 July 2008
+  Last Modified: 14 Oct 2008
   Number: 9
-  Version: 28
+  Version: 29

 =head1 Overview

@@ -362,7 +362,7 @@
     @@x <==  %hash.keys.grep: {/^\d+$/};
     @@x <== =<>;
     @@x <== 1..*;
-    @@x <== gather { loop { take rand 100 } };
+    @@x <== gather { loop { take 100.rand } };

     @array{@@x}

@@ -374,7 +374,7 @@
     @x <==  %hash.keys.grep: {/^\d+$/};
     @x <== =<>;
     @x <== 1..*;
-    @x <== gather { loop { take rand 100 } };
+    @x <== gather { loop { take 100.rand } };

     @array{@@x}  # multidimensional
     @array{@x}   # flattened
@@ -1206,7 +1206,7 @@
 In Perl 6 these read-only operations are indeed non-destructive:

     my %hash;
-    exists %hash<foo><bar>; # %hash is still empty
+    %hash<foo><bar> :exists; # %hash is still empty

 But these bindings I<do> autovivify:

Modified: doc/trunk/design/syn/S12.pod
=========================================================================== ===
--- doc/trunk/design/syn/S12.pod        (original)
+++ doc/trunk/design/syn/S12.pod        Tue Oct 14 17:14:18 2008
@@ -12,9 +12,9 @@

   Maintainer: Larry Wall <la...@wall.org>
   Date: 27 Oct 2004
-  Last Modified: 21 Aug 2008
+  Last Modified: 14 Oct 2008
   Number: 12
-  Version: 63
+  Version: 64

 =head1 Overview

@@ -1787,6 +1787,26 @@
 type C<bit>.  Never compare a value to "C<true>", or even "C<True>".
 Just use it in a boolean context.

+Enum types (and perhaps certain other finite, enumerable types such
+as finite ranges) define a C<.pick> method on the protoobject of
+that type.  Hence:
+
+    my enum CoinFace <Heads Tails>;
+    CoinFace.pick
+
+returns C<Heads> or C<Tails> with equal probability, and
+
+    Month.pick(*)
+
+will return the months in random order.  Presumably
+
+    StandardPlayingCards.pick(5)
+
+might return a Royal Flush, but a Full House is much
+more likely.  It can never return Five Aces, since the pick
+is done without replacement.  (If it I<does> return Five Aces,
+it's time to walk away.)
+
 =head1 Open vs Closed Classes

 By default, all classes in Perl are non-final, which means