Proof of Equality for B=Int(B)∪bd(B) in Metric Space A

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Let A be a metric space and B be a compact subset of A.
Is it true that an equality B = Int(B) [itex]\cup[/itex] bd(B) holds??
 
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In a metric space every compact set is closed (actually in every topological space). What does that tell you about its boundary points?
 
Boundary point is also limit point, right?
Then it belongs to B since B is closed?
 
HallsofIvy said:
In a metric space every compact set is closed (actually in every topological space).

Hausdorff topological space, no? Which does include metric spaces, I admit.