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[svn:perl6-synopsis] r13585 - doc/trunk/design/syn

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Feb 14, 2007, 2:07:02 AM2/14/07
to perl6-l...@perl.org
Author: larry
Date: Tue Feb 13 23:07:00 2007
New Revision: 13585

Modified:
doc/trunk/design/syn/S02.pod

Log:
Got rid of quote declarator. Just use a macro.


Modified: doc/trunk/design/syn/S02.pod
==============================================================================
--- doc/trunk/design/syn/S02.pod (original)
+++ doc/trunk/design/syn/S02.pod Tue Feb 13 23:07:00 2007
@@ -12,9 +12,9 @@

Maintainer: Larry Wall <la...@wall.org>
Date: 10 Aug 2004
- Last Modified: 11 Feb 2007
+ Last Modified: 13 Feb 2007
Number: 2
- Version: 86
+ Version: 87

This document summarizes Apocalypse 2, which covers small-scale
lexical items and typological issues. (These Synopses also contain
@@ -1958,67 +1958,20 @@
:trans Parse as transliteration
:code Quasiquoting

-Ordinarily the colon is required on adverbs, but the C<quote> declarator
-allows you to combine any of the existing adverbial forms above
-without an intervening colon:
+You may omit the first colon by joining an initial 'Q', 'q', or 'qq' with
+a single short form adverb, which produces forms like:

- quote qw; # declare a P5-esque qw// meaning q:w
- quote Qc; # Q:c//, interpolate only closures
+ qw /a b c/; # P5-esque qw// meaning q:w
+ Qc '...{$x}...'; # Q:c//, interpolate only closures
+ qqx/$cmd @args/ # equivalent to P5's qx//

-Actually, those two are already assumed, because you get all of the
-forms that use a single character modifier predeclared for free. (Note
-this means that C<qx//> doesn't intepolate.)
+(Note that C<qx//> doesn't intepolate.)

-If you want to abbreviate further, you may also give an explicit
-definition as either a string or quasiquote:
+If you want to abbreviate further, just define a macro:

- quote qx = 'qq:x'; # equivalent to P5's qx//
- quote qTO = 'qq:x:w:to'; # qq:x:w:to//
- quote circumfix:<❰ ❱> = q:code{ .quoteharder }; # or some such...
-
-In particular, all these forms disable the lookahead for an adverbial argument,
-as if there were a space after the keyword. So although
-
- q:s($foo)
-
-will misinterpret C<$foo> as the C<:s> argument,
-
- qs(stuff)
-
-has the advantage of misinterpreting it as the argument to the C<qs()>
-function instead. C<:)>
-
-But parens are special that way. (Even C<q()> is assumed to be a
-function call rather than a quote.) Other bracketing characters are
-special only if they can be mistaken for adverbial arguments, so
-
- qs[stuff]
-
-is fine, and means
-
- q:s /stuff/
-
-while
-
- q:s[stuff]
-
-also happens to work because quote adverbs only allow the paren form of
-bracketed adverbs.
-
-If this is all too much of a hardship, you can define your own quote
-adverbs and operators as standard macros. The main difference is that,
-unlike
-
- quote qs = 'q:s';
-
-declaring something like
-
- macro qs { 'q:s' }
-
-does I<not> disable the subsequent search for a parenthesized argument
-to C<:n>. To get the equivalent, you need to add a space:
-
- macro qs { 'q:s ' }
+ macro qx { 'qq:x ' } # equivalent to P5's qx//
+ macro qTO { 'qq:x:w:to ' } # qq:x:w:to//
+ macro circumfix:<❰ ❱> ($expr) { q:code{ $expr.quoteharder } }

All the uppercase adverbs are reserved for user-defined quotes.
All Unicode delimiters above Latin-1 are reserved for user-defined quotes.

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