From dff42354bc083dcb1363cd78f521dad9284ac2f9 Mon Sep 17 00:00:00 2001
From: Blake-Madden <66873089+Blake-Madden@users.noreply.github.com>
Date: Tue, 28 May 2024 11:32:43 -0400
Subject: [PATCH] Add copy construction support Explain that each thread should
 have its own parser object.

---
 README.md             |  2 +-
 docs/manual/index.qmd |  2 +-
 tinyexpr.h            | 18 ++++++++++++++++--
 3 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 75483ac..41e2f4d 100644
--- a/README.md
+++ b/README.md
@@ -53,7 +53,7 @@ Note: for current users of *TinyExpr++*, please see the [compatibility advisory]
 - Supports C and C++ style comments within math expressions.
 - Released under the zlib license - free for nearly any use.
 - Easy to use and integrate with your code.
-- Thread-safe; parser is in a self-contained object.
+- Thread-safe; parser can be constructed as per thread objects.
 
 ## Changes from TinyExpr
 
diff --git a/docs/manual/index.qmd b/docs/manual/index.qmd
index 71397fa..591f3e5 100644
--- a/docs/manual/index.qmd
+++ b/docs/manual/index.qmd
@@ -46,4 +46,4 @@ It's open-source, free, easy-to-use, and self-contained in a single source and h
 - Can be configured to use `double`, `long double`, or [`float`](#te-float) for its calculations.
 - Released under the zlib license - free for nearly any use.
 - Easy to use and integrate with your code.
-- Thread-safe; parser is in a self-contained object.
+- Thread-safe; parser can be constructed as per thread objects.
diff --git a/tinyexpr.h b/tinyexpr.h
index e763ad7..0a5efc8 100644
--- a/tinyexpr.h
+++ b/tinyexpr.h
@@ -246,9 +246,23 @@ class te_parser
     /// @private
     te_parser() = default;
     /// @private
-    te_parser(const te_parser&) = delete;
+    te_parser(const te_parser& that)
+        {
+        m_customFuncsAndVars = that.m_customFuncsAndVars;
+        m_unknownSymbolResolve = that.m_unknownSymbolResolve;
+        m_keepResolvedVarialbes = that.m_keepResolvedVarialbes;
+        m_decimalSeparator = that.m_decimalSeparator;
+        m_listSeparator = that.m_listSeparator;
+        }
     /// @private
-    te_parser& operator=(const te_parser&) = delete;
+    te_parser& operator=(const te_parser& that)
+        {
+        m_customFuncsAndVars = that.m_customFuncsAndVars;
+        m_unknownSymbolResolve = that.m_unknownSymbolResolve;
+        m_keepResolvedVarialbes = that.m_keepResolvedVarialbes;
+        m_decimalSeparator = that.m_decimalSeparator;
+        m_listSeparator = that.m_listSeparator;
+        }
 
     /// @private
     ~te_parser() { te_free(m_compiledExpression); }