Bourbaki

Theorem 2

Tag 0BG3, permanent. Cite it as [Bourbaki, Tag 0BG3].

General Topology, chapter II, § 4. Relations between uniform spaces and compact spaces

Every continuous mapping ff of a compact space XX into a uniform space X′X' is uniformly continuous.

Let g=f×fg = f \times f, then gg is continuous on X×XX \times X (Chapter I, § 4, no. 1, Proposition 1, Corollary 1); hence for each open entourage V′V' of X′X', g−1‾(V′)\overline{g^{-1}}(V') is an open subset of X×XX \times X, which evidently contains the diagonal. The theorem thus follows from Theorem 1, since the open entourages of X′X' form a fundamental system of entourages (§ 1, no. 2, Proposition 2, Corollary 2).

Under the hypotheses of Theorem 2, the restriction of ff to any subspace AA of XX is uniformly continuous; hence (§ 3, no. 6, Theorem 2):

Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.

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