Re: [svn:perl6-synopsis] r9727 - doc/trunk/design/syn
On Sat, Jul 01, 2006 at 03:31:52PM +0300, Markus Laire wrote: : On 7/1/06, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: : >+In particular, these forms disable the lookahead for an adverbial : >argument, : >+so while : >+ : >+q:n($foo) : >+ : >+will misinterpret C<$foo> as the C<:n> argument, : >+ : >+qn(stuff) : >+ : >+has the advantage of misinterpreting it as the argument to the C : >+function instead. C<:)> : >+ : >+But parens are special that way. Other bracketing characters are special : >+only if they can be mistaken for adverbial arguments, so : >+ : >+qn[stuff] : >+ : >+is fine, while : >+ : >+q:n[stuff] : >+ : >+is not. Basically, just don't use parens for quote delimiters, and always : >+put a space after your adverbs. : : Why q:n[stuff] is not fine? Shouldn't that pass [stuff] to adverb n? That's what it does. But it's not fine if you expected [...] to delimit the quoted string instead. : Also, in what way are parens special? : Doesn't qn(stuff) and qn[stuff] both mean same thing? Nope, qn(stuff) is always a function call. q(foo) is always a function call, not a quote. : And both q:n(stuff) and q:n[stuff] pass something to adverb n. (First : passes stuff, second passes [stuff]) That is correct. My intent with the quote declarator however is that there be an implicit space after it, so the n on the end of qn no longer functions as an adverb, at least in terms of looking for a subsequent argument. I will attempt to clarify the distinction between quotes and ordinary macros. Thanks. Larry
Re: [svn:perl6-synopsis] r9727 - doc/trunk/design/syn
On 7/1/06, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: +In particular, these forms disable the lookahead for an adverbial argument, +so while + +q:n($foo) + +will misinterpret C<$foo> as the C<:n> argument, + +qn(stuff) + +has the advantage of misinterpreting it as the argument to the C +function instead. C<:)> + +But parens are special that way. Other bracketing characters are special +only if they can be mistaken for adverbial arguments, so + +qn[stuff] + +is fine, while + +q:n[stuff] + +is not. Basically, just don't use parens for quote delimiters, and always +put a space after your adverbs. Why q:n[stuff] is not fine? Shouldn't that pass [stuff] to adverb n? Also, in what way are parens special? Doesn't qn(stuff) and qn[stuff] both mean same thing? And both q:n(stuff) and q:n[stuff] pass something to adverb n. (First passes stuff, second passes [stuff]) -- Markus Laire
[svn:perl6-synopsis] r9727 - doc/trunk/design/syn
Author: larry
Date: Fri Jun 30 15:17:55 2006
New Revision: 9727
Modified:
doc/trunk/design/syn/S02.pod
Log:
Revised quote declarator.
Modified: doc/trunk/design/syn/S02.pod
==
--- doc/trunk/design/syn/S02.pod(original)
+++ doc/trunk/design/syn/S02.podFri Jun 30 15:17:55 2006
@@ -14,7 +14,7 @@
Date: 10 Aug 2004
Last Modified: 30 Jun 2006
Number: 2
- Version: 46
+ Version: 47
This document summarizes Apocalypse 2, which covers small-scale
lexical items and typological issues. (These Synopses also contain
@@ -1344,21 +1344,50 @@
:f :function Interpolate & calls
:c :closureInterpolate {...} expressions
:b :backslash Interpolate \n, \t, etc. (implies :q at least)
+:code Quasiquoting
-[Conjectural: Ordinarily the colon is required on adverbs, but the
-"quote" declarator allows you to combine any of the existing adverbial
-forms above without an intervening colon:
-
-quote qw; # declare a P5-esque qw//
-quote qqx; # equivalent to P5's qx//
-quote qn; # completely raw quote qn//
-quote qnc; # interpolate only closures
-quote qqxwto; # qq:x:w:to//
+Ordinarily the colon is required on adverbs, but the C declarator
+allows you to combine any of the existing adverbial forms above
+without an intervening colon:
-]
+quote qw; # declare a P5-esque qw// meaning q:w
+quote qn; # completely raw quote qn//
+quote qnc; # q:n:c//, interpolate only closures
+
+If you want to abbreviate further, you may also give an explicit
+definition as either a string or quasiquote:
+
+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, these forms disable the lookahead for an adverbial argument,
+so while
+
+q:n($foo)
+
+will misinterpret C<$foo> as the C<:n> argument,
+
+qn(stuff)
+
+has the advantage of misinterpreting it as the argument to the C
+function instead. C<:)>
+
+But parens are special that way. Other bracketing characters are special
+only if they can be mistaken for adverbial arguments, so
+
+qn[stuff]
+
+is fine, while
+
+q:n[stuff]
+
+is not. Basically, just don't use parens for quote delimiters, and always
+put a space after your adverbs.
If this is all too much of a hardship, you can define your own quote
-adverbs and operators. All the uppercase adverbs are reserved for
+adverbs and operators as standard macros.
+All the uppercase adverbs are reserved for
user-defined quotes. All of Unicode above Latin-1 is reserved for
user-defined quotes.
