From f615f0aeaec21342e96ec6d5f10e9be65ad3e916 Mon Sep 17 00:00:00 2001
From: wangzheng <wangz@oasisrobotics.tech>
Date: Thu, 12 Dec 2024 17:31:46 +0800
Subject: [PATCH] fix script parse error while 'A==-1'

---
 examples/t09_scripting.cpp                       | 2 +-
 include/behaviortree_cpp/scripting/operators.hpp | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/examples/t09_scripting.cpp b/examples/t09_scripting.cpp
index c8be35c5a..bca9774bb 100644
--- a/examples/t09_scripting.cpp
+++ b/examples/t09_scripting.cpp
@@ -10,7 +10,7 @@ static const char* xml_text = R"(
         <Sequence>
             <Script code=" msg:='hello world' " />
             <Script code=" A:=THE_ANSWER; B:=3.14; color:=RED " />
-            <Precondition if="A>B && color != BLUE" else="FAILURE">
+            <Precondition if="A>-B && color != BLUE" else="FAILURE">
                 <Sequence>
                   <SaySomething message="{A}"/>
                   <SaySomething message="{B}"/>
diff --git a/include/behaviortree_cpp/scripting/operators.hpp b/include/behaviortree_cpp/scripting/operators.hpp
index 30c4844ea..f44b0d4ea 100644
--- a/include/behaviortree_cpp/scripting/operators.hpp
+++ b/include/behaviortree_cpp/scripting/operators.hpp
@@ -796,9 +796,9 @@ struct Expression : lexy::expression_production
                                dsl::op<Ast::ExprComparison::greater_equal>(LEXY_LIT(">"
                                                                                     "="));
 
-    // The use of dsl::groups ensures that an expression can either contain math or bit
+    // The use of dsl::groups ensures that an expression can either contain math or bit or string
     // operators. Mixing requires parenthesis.
-    using operand = dsl::groups<math_sum, bit_or>;
+    using operand = dsl::groups<math_sum, bit_or, string_concat>;
   };
 
   // Logical operators,  || and &&
@@ -808,7 +808,7 @@ struct Expression : lexy::expression_production
         dsl::op<Ast::ExprBinaryArithmetic::logic_or>(LEXY_LIT("||")) /
         dsl::op<Ast::ExprBinaryArithmetic::logic_and>(LEXY_LIT("&&"));
 
-    using operand = dsl::groups<string_concat, comparison>;
+    using operand = comparison;
   };
 
   // x ? y : z