refine ⟨IccExtend hab.le (restrict (Icc a b) f), h.restrict.Icc_extend', ?_⟩
a b : ℝ
hab : a < b
f : ℝ → ℝ
h : ContinuousOn f (Icc a b)
⊢ ∃ g, Continuous g ∧ EqOn g f (Icc a b)
a b : ℝ
hab : a < b
f : ℝ → ℝ
h : ContinuousOn f (Icc a b)
⊢ EqOn (IccExtend ⋯ (restrict (Icc a b) f)) f (Icc a b)