From f83342e71722208942f1f4d450717e3282b32216 Mon Sep 17 00:00:00 2001
From: Ivo Hedtke <ivo.hedtke@dbschenker.com>
Date: Wed, 22 Nov 2023 15:41:21 +0100
Subject: [PATCH 1/2] Allow the construction of constant linear expressions
 without narrowing warnings

---
 include/scippp/lin_expr.hpp | 7 ++++++-
 source/lin_expr.cpp         | 5 -----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/include/scippp/lin_expr.hpp b/include/scippp/lin_expr.hpp
index cdb0813f..0d8e845e 100644
--- a/include/scippp/lin_expr.hpp
+++ b/include/scippp/lin_expr.hpp
@@ -29,9 +29,14 @@ class LinExpr {
      * Creates a linear expression with no variables.
      * @since 1.0.0
      * @remark This is on purpose not an explicit c'tor to allow expressions like x <= 1.
+     * @tparam Arithmetic type that will be casted to \c double via \c static_cast
      * @param constant Constant term to set.
      */
-    LinExpr(double constant);
+    template <typename Arithmetic, std::enable_if_t<std::is_arithmetic_v<Arithmetic>, bool> = true>
+    LinExpr(Arithmetic constant)
+        : m_constant { static_cast<double>(constant) }
+    {
+    }
     /**
      * Creates a linear expression with zero as constant the given variable with coefficient one.
      * @since 1.0.0
diff --git a/source/lin_expr.cpp b/source/lin_expr.cpp
index c3374576..858aa442 100644
--- a/source/lin_expr.cpp
+++ b/source/lin_expr.cpp
@@ -2,11 +2,6 @@
 
 namespace scippp {
 
-LinExpr::LinExpr(double constant)
-    : m_constant { constant }
-{
-}
-
 LinExpr::LinExpr(const Var& var)
     : m_vars { var }
     , m_coeffs(1, 1)

From 4baa55ea58d42cefe73f54da9fbe2218f46a81c0 Mon Sep 17 00:00:00 2001
From: Ivo Hedtke <ivo.hedtke@dbschenker.com>
Date: Wed, 22 Nov 2023 15:52:22 +0100
Subject: [PATCH 2/2] Add explicit warning on narrowing in LinExpr

---
 include/scippp/lin_expr.hpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/scippp/lin_expr.hpp b/include/scippp/lin_expr.hpp
index 0d8e845e..e0c7f6f7 100644
--- a/include/scippp/lin_expr.hpp
+++ b/include/scippp/lin_expr.hpp
@@ -29,7 +29,8 @@ class LinExpr {
      * Creates a linear expression with no variables.
      * @since 1.0.0
      * @remark This is on purpose not an explicit c'tor to allow expressions like x <= 1.
-     * @tparam Arithmetic type that will be casted to \c double via \c static_cast
+     * @tparam Arithmetic type that will be casted to \c double.
+     * @warning \c Arithmetic is casted to \c double without creating a narrowing warning!
      * @param constant Constant term to set.
      */
     template <typename Arithmetic, std::enable_if_t<std::is_arithmetic_v<Arithmetic>, bool> = true>