From c84ad4e228fc2513bcc33b367506705004859cac Mon Sep 17 00:00:00 2001
From: Jukka Aho <ahojukka5@gmail.com>
Date: Wed, 19 Nov 2025 10:03:45 +0200
Subject: [PATCH] feat(materials): Declare LinearElastic as
 StatelessConstantTangent

- Add material_behavior(::LinearElastic) = StatelessConstantTangent()
- Enables generic integration to optimize constant tangent case
- Single line trait declaration, zero code duplication
- Integration computes tangent once and reuses for all IPs
---
 src/materials/linear_elastic.jl | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/materials/linear_elastic.jl b/src/materials/linear_elastic.jl
index 80cf68c..6a58875 100644
--- a/src/materials/linear_elastic.jl
+++ b/src/materials/linear_elastic.jl
@@ -68,6 +68,9 @@ steel = LinearElastic(E=200e9, ν=0.3)
 """
 LinearElastic(; E, ν) = LinearElastic(Float64(E), Float64(ν))
 
+# Trait declaration: LinearElastic has constant tangent modulus
+material_behavior(::LinearElastic) = StatelessConstantTangent()
+
 """
     λ(material::LinearElastic) -> Float64