Use wantarray inside the sub to tell how it was called. That will be undef for void context, true for list context, and false (but defined) for scalar context: 
sub name {
  ...
  if (not defined wantarray) {
    # do your void context behavior
  }
  elsif (wantarray) {
    # do your scalar context behavior
  }
  else {
    # do your list context behavior
  }
}

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Phil

In reply to Re: Scalar and void subroutines by philcrow
in thread Scalar and void subroutines by eff_i_g

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