Author: larry
Date: Sun May 14 10:39:58 2006
New Revision: 9253
Modified:
doc/trunk/design/syn/S02.pod
doc/trunk/design/syn/S06.pod
Log:
Got rid of default @@_ array and postfix ==>.
May now pipe to * multiple times.
Pipe batches sent to * are received with *** now.
(*** also specifies receiver location for current pointy end.)
Modified: doc/trunk/design/syn/S02.pod
==============================================================================
--- doc/trunk/design/syn/S02.pod (original)
+++ doc/trunk/design/syn/S02.pod Sun May 14 10:39:58 2006
@@ -12,9 +12,9 @@
Maintainer: Larry Wall <[EMAIL PROTECTED]>
Date: 10 Aug 2004
- Last Modified: 12 May 2006
+ Last Modified: 14 May 2006
Number: 2
- Version: 40
+ Version: 41
This document summarizes Apocalypse 2, which covers small-scale
lexical items and typological issues. (These Synopses also contain
@@ -506,6 +506,12 @@
is effectively immutable, the optimizer is free to recognize C<*>
and optimize in the context of what operator it is being passed to.
+A variant of C<*> is the C<**> term. It is generally understood to
+be a multidimension form of C<*> when that makes sense.
+
+The C<***> variant serves as the insertion point of a list of pipes.
+That insertion point may be targeted by piping to C<*>. See S06.
+
Other uses for C<*> will doubtless suggest themselves over time. These
can be given meaning via the MMD system, if not the compiler. In general
a C<Whatever> should be interpreted as maximizing the degrees of freedom
Modified: doc/trunk/design/syn/S06.pod
==============================================================================
--- doc/trunk/design/syn/S06.pod (original)
+++ doc/trunk/design/syn/S06.pod Sun May 14 10:39:58 2006
@@ -13,9 +13,9 @@
Maintainer: Larry Wall <[EMAIL PROTECTED]>
Date: 21 Mar 2003
- Last Modified: 13 May 2006
+ Last Modified: 14 May 2006
Number: 6
- Version: 34
+ Version: 35
This document summarizes Apocalypse 6, which covers subroutines and the
@@ -860,6 +860,25 @@
operation, it must be something else that can be interpreted as a
list receiver.
+Any list operator is considered a variadic operation, so ordinarily
+a list operator adds any piped input to the end of its list.
+But sometimes you want to interpolate elsewhere, so the C<***> term
+may be used to indicating the target of a pipe without the use of a
+temporary array:
+
+ foo() ==> say ***, " is what I meant";
+ bar() ==> ***.baz();
+
+Piping to the C<*> "whatever" term is considered a pipe to the lexically
+following C<***> term:
+
+ 0..* ==> *;
+ 'a'..* ==> *;
+ pidigits() ==> *;
+
+ # outputs "(0, 'a', 3)\n"...
+ for zip(***) { .perl.say }
+
You may use a variable (or variable declaration) as a receiver, in
which case the list value is bound as the "todo" of the variable.
Do not think of it as an assignment, nor as an ordinary binding.
@@ -979,19 +998,8 @@
In particular, you can use C<@@foo> to interpolate a multidimensional slice
in an array or hash subscript.
-Every lexical scope can use its own implicitly declared C<@_> variable
-as the default receiver. So instead of using C<@@foo> above you can
-just say
-
- 0..* ==> ;
- 'a'..* ==> ;
- pidigits() ==> ;
-
- # outputs "(0, 'a', 3)\n"...
- for zip(@@_) { .perl.say }
-
-If C<@@_> is currently empty, then C<for zip(@@_) {...}> would act on a
-zero-dimensional slice (i.e. C<for (zip) {...}>), and output nothing
+If C<@@foo> is currently empty, then C<for zip(@@foo) {...}> acts on a
+zero-dimensional slice (i.e. C<for (zip) {...}>), and outputs nothing
at all.
Note that with the current definition, the order of pipes is preserved
@@ -999,14 +1007,14 @@
So
- ('a'..*; 0..*) ==> ;
- for zip(@@_ <== @foo) -> [$a, $i, $x] { ...}
+ ('a'..*; 0..*) ==> *;
+ for zip(*** <== @foo) -> [$a, $i, $x] { ...}
is the same as
- 'a'..* ==> ;
- 0..* ==> ;
- for zip(@@_ <== @foo) -> [$a, $i, $x] { ...}
+ 'a'..* ==> *;
+ 0..* ==> *;
+ for zip(*** <== @foo) -> [$a, $i, $x] { ...}
which is the same as
@@ -1014,14 +1022,14 @@
And
- @foo ==> ;
- 0..* ==> ;
- for each(@@_) -> $x, $i { ...}
+ @foo ==> *;
+ 0..* ==> *;
+ for each(***) -> $x, $i { ...}
is the same as
- 0..* ==> ;
- for each(@foo; @@_) -> $x, $i { ...}
+ 0..* ==> *;
+ for each(@foo; ***) -> $x, $i { ...}
which is the same as
