From c5e9cf215517aafc1a55b20d9f4dde7f75f90293 Mon Sep 17 00:00:00 2001
From: MadMaurice <madmaurice@zom.bi>
Date: Sat, 10 Apr 2021 01:26:07 +0200
Subject: [PATCH] Fix lexer: Strings can be empty

---
 lib/Minilisp.pm | 2 +-
 t/strings.t     | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/Minilisp.pm b/lib/Minilisp.pm
index a5d042f..4186e56 100644
--- a/lib/Minilisp.pm
+++ b/lib/Minilisp.pm
@@ -75,7 +75,7 @@ sub tokenize {
             value => $1,
           };
         }
-      elsif($str =~ s/^"(([^"\\]|\\.)+)"//)
+      elsif($str =~ s/^"(([^"\\]|\\.)*)"//)
         {
           $debug->("String '$1'");
           my $value = $1;
diff --git a/t/strings.t b/t/strings.t
index 9533044..9714cae 100644
--- a/t/strings.t
+++ b/t/strings.t
@@ -1,7 +1,9 @@
-(plan 4)
+(plan 5)
 
 (expect "length of string" (= (length "hello") 5))
 
+(expect "empty strings" (= (length "") 0))
+
 (expect "string-upcase" (string= (string-upcase "helLo") "HELLO"))
 
 (expect "string-downcase" (string= (string-downcase "HEllO") "hello"))