Implement backreferences.

Raku · Sep 29, 2012 · 5c4d6b2 · 5c4d6b2
1 parent 9a42dc5
commit 5c4d6b2
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Showing 3 changed files with 12 additions and 3 deletions.
diff --git a/src/QRegex/P5Regex/Actions.nqp b/src/QRegex/P5Regex/Actions.nqp
@@ -164,8 +164,15 @@ class QRegex::P5Regex::Actions is HLL::Actions {
     }
 
     method p5backslash:sym<misc>($/) {
-        my $qast := QAST::Regex.new( ~$/ , :rxtype('literal'), :node($/) );
-        make $qast;
+        if $<litchar> {
+            make QAST::Regex.new( ~$<litchar> , :rxtype('literal'), :node($/) );
+        }
+        else {
+            make QAST::Regex.new( :rxtype<subrule>, :subtype<method>, :node($/),
+                QAST::Node.new(
+                    QAST::SVal.new( :value('!BACKREF') ),
+                    QAST::SVal.new( :value(~$<number> - 1) ) ) );
+        }
     }
 
     method p5quantifier:sym<*>($/) {

diff --git a/src/QRegex/P5Regex/Grammar.nqp b/src/QRegex/P5Regex/Grammar.nqp
@@ -83,7 +83,7 @@ grammar QRegex::P5Regex::Grammar is HLL::Grammar {
 
     token p5backslash:sym<b> { $<sym>=[<[bB]>] }
     token p5backslash:sym<s> { $<sym>=[<[dDnNsSwW]>] }
-    token p5backslash:sym<misc> { \W }
+    token p5backslash:sym<misc> { $<litchar>=(\W) | $<number>=(\d+) }
     token p5backslash:sym<oops> { <.panic: "Unrecognized Perl 5 regex backslash sequence"> }
 
     proto token p5assertion { <...> }

diff --git a/t/p5regex/rx_captures b/t/p5regex/rx_captures
@@ -14,3 +14,5 @@ d()ef		zzzabcdefzzz	y			empty capture
 (a)b(c)		abc		y			multiple matches
 (a)b(c)		abc	<mob[0]: a @ 0>	basic $0
 (a)b(c)		abc	<mob[1]: c @ 2>	basic $1
+b(.)\1				bookkeeper	y			backreference
+b(.)\1(.)\2				bookkeeper	y			backreference