Just for fun, a lookaround solution. When you find a space preceded by a space, or a space followed by a space, replace it: 
s/(?<= ) | (?= )/&nbsp;/g;

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The PerlMonk tr/// Advocate

In reply to Re: Looking for white spaces between words by Roy Johnson
in thread Looking for white spaces between words by TASdvlper

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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