Minor cleanup

Nevanlinna/holomorphic_examples.lean

@@ -1,6 +1,7 @@
 import Nevanlinna.complexHarmonic
 import Nevanlinna.holomorphicAt
 import Nevanlinna.holomorphic_primitive
+import Nevanlinna.mathlibAddOn
 
 
 theorem CauchyRiemann₆
@@ -97,9 +98,11 @@ theorem CauchyRiemann₇
 
 
 
+
 /-
 
-A harmonic, real-valued function on ℂ is the real part of a suitable holomorphic function.
+A harmonic, real-valued function on ℂ is the real part of a suitable holomorphic
+function.
 
 -/
 
@@ -136,9 +139,7 @@ theorem harmonic_is_realOfHolomorphic
     dsimp [g]
     apply ContDiff.sub
     exact reg₁f_1
-    have : Complex.I • f_I = fun x ↦ Complex.I • f_I x := rfl
+    apply ContDiff.const_smul'
-    rw [this]
-    apply ContDiff.const_smul
     exact reg₁f_I
 
   have reg₁ : Differentiable ℂ g := by
@@ -181,16 +182,12 @@ theorem harmonic_is_realOfHolomorphic
       -- Differentiable ℝ f_1
       exact reg₁f_1.differentiable le_rfl
       -- Differentiable ℝ (Complex.I • f_I)
-      have : Complex.I • f_I = fun x ↦ Complex.I • f_I x := rfl
+      apply Differentiable.const_smul'
-      rw [this]
-      apply Differentiable.const_smul
       exact reg₁f_I.differentiable le_rfl
       -- Differentiable ℝ f_1
       exact reg₁f_1.differentiable le_rfl
       -- Differentiable ℝ (Complex.I • f_I)
-      have : Complex.I • f_I = fun x ↦ Complex.I • f_I x := rfl
+      apply Differentiable.const_smul'
-      rw [this]
-      apply Differentiable.const_smul
       exact reg₁f_I.differentiable le_rfl
 
   let F := fun z ↦ (primitive 0 g) z + f 0
@@ -253,4 +250,3 @@ theorem harmonic_is_realOfHolomorphic
     fun_prop
     -- DifferentiableAt ℝ F x
     exact regF.restrictScalars ℝ x
-

Nevanlinna/mathlibAddOn.lean

@@ -0,0 +1,35 @@
+import Mathlib.Analysis.Calculus.ContDiff.Basic
+import Mathlib.Analysis.Calculus.FDeriv.Add
+
+variable {𝕜 : Type*} [NontriviallyNormedField 𝕜]
+variable {E : Type*} [NormedAddCommGroup E] [NormedSpace 𝕜 E]
+variable {F : Type*} [NormedAddCommGroup F] [NormedSpace 𝕜 F]
+variable {G : Type*} [NormedAddCommGroup G] [NormedSpace 𝕜 G]
+variable {G' : Type*} [NormedAddCommGroup G'] [NormedSpace 𝕜 G']
+variable {f f₀ f₁ g : E → F}
+variable {f' f₀' f₁' g' : E →L[𝕜] F}
+variable (e : E →L[𝕜] F)
+variable {x : E}
+variable {s t : Set E}
+variable {L L₁ L₂ : Filter E}
+
+variable {R : Type*} [Semiring R] [Module R F] [SMulCommClass 𝕜 R F] [ContinuousConstSMul R F]
+
+
+-- import Mathlib.Analysis.Calculus.FDeriv.Add
+
+@[fun_prop]
+theorem Differentiable.const_smul' (h : Differentiable 𝕜 f) (c : R) :
+    Differentiable 𝕜 (c • f) := by
+  have : c • f = fun x ↦ c • f x := rfl
+  rw [this]
+  exact Differentiable.const_smul h c
+
+
+-- Mathlib.Analysis.Calculus.ContDiff.Basic
+
+theorem ContDiff.const_smul' {f : E → F} (c : R) (hf : ContDiff 𝕜 n f) :
+    ContDiff 𝕜 n (c • f) := by
+  have : c • f = fun x ↦ c • f x := rfl
+  rw [this]
+  exact ContDiff.const_smul c hf