Modified:
doc/trunk/design/syn/S02.pod
Log:
Made one-pass parsing rule explicit so that tests can refer to it.
Modified: doc/trunk/design/syn/S02.pod
==============================================================================
--- doc/trunk/design/syn/S02.pod (original)
+++ doc/trunk/design/syn/S02.pod Mon Feb 26 11:05:31 2007
@@ -12,9 +12,9 @@
Maintainer: Larry Wall <la...@wall.org>
Date: 10 Aug 2004
- Last Modified: 22 Feb 2007
+ Last Modified: 26 Feb 2007
Number: 2
- Version: 89
+ Version: 90
This document summarizes Apocalypse 2, which covers small-scale
lexical items and typological issues. (These Synopses also contain
@@ -23,6 +23,26 @@
These updates are not marked--if a Synopsis disagrees with its
Apocalypse, assume the Synopsis is correct.)
+=head1 One-pass parsing
+
+To the extent allowed by sublanguages parsers, Perl is parsed using a
+one-pass, predictive parser. That is, lookahead of more than one
+"longest token" is discouraged. The currently known exceptions to
+this are where the parser must:
+
+=over 4
+
+=item *
+
+Locate the end of interpolated expressions that begin with a sigil
+and might or might not end with brackets.
+
+=item *
+
+Recognize that a reduce operator is not really beginning a C<[...]> composer.
+
+=back
+
=head1 Lexical Conventions
=over 4