title: Are there any "penalties" for defining a struct inside a function?
body: <p>Just out of curiosity.. </p>
  
  <p>As the titles says: <strong>are there any "penalties" for defining a struct inside a function?</strong> (like <em>performance, memory, bad programming practice</em>, etc.)</p>
  
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  <p>P.S. I know, that it's a common practice to define (NON-template) functors inside functions, but still..)</p>