Handle simple binding aliases.

perl6 · Oct 13, 2009 · 4481429 · 4481429
1 parent 76c694d
commit 4481429
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diff --git a/src/Regex/P6Regex/Actions.pm b/src/Regex/P6Regex/Actions.pm
@@ -168,6 +168,19 @@ method metachar:sym<assert>($/) {
     make $<assertion>.ast;
 }
 
+method metachar:sym<var>($/) {
+    my $past;
+    my $name := $<pos> ?? +$<pos> !! ~$<name>;
+    if $<quantified_atom> {
+        $past := $<quantified_atom>[0].ast;
+        if $past.pasttype eq 'subrule' { 
+            $past.subtype('capture');
+            $past.name($name); 
+        }
+    }
+    make $past;
+}
+
 method backslash:sym<w>($/) {
     my $subtype := ~$<sym> eq 'n' ?? 'nl' !! ~$<sym>;
     my $past := PAST::Regex.new( :pasttype('charclass'), :subtype($subtype) );
@@ -329,6 +342,7 @@ sub capnames($ast, $count) {
             $ast.name($count);
             $count := $count + 1;
         }
+        elsif $ast.name eq '0' || $ast.name > 0 { $count := $ast.name + 1; }
         %capnames{$ast.name} := 1;
     }
     elsif $pasttype eq 'quant' {

diff --git a/src/Regex/P6Regex/Grammar.pm b/src/Regex/P6Regex/Grammar.pm
@@ -71,6 +71,16 @@ grammar Regex::P6Regex::Grammar is PCT::Grammar;
         {*}
     }
 
+    token metachar:sym<var> {
+        [ 
+        | '$<' $<name>=[<-[>]>+] '>' 
+        | '$' $<pos>=[\d+]
+        ]
+
+        [ <.ws> '=' <.ws> <quantified_atom> ]?
+        {*}
+    }
+
     # proto token backslash { <...> }
     token backslash:sym<w> { $<sym>=[<[dswnDSWN]>] {*} }
     token backslash:sym<b> { $<sym>=[<[bB]>] {*} }