$VERSION = eval $VERSION;？

Perl 
our $VERSION = '0.15';
$VERSION = eval $VERSION;    ## no critic

これって何の意味があるんだろう？

$ perl -MDevel::Peek -e 'our $VERSION = "0.15";Dump($VERSION);$VERSION = eval $VERSION;Dump($VERSION)'
SV = PV(0x10011dc0) at 0x1002ee28
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x10025c10 "0.15"\0
  CUR = 4
  LEN = 5
SV = PVNV(0x10014398) at 0x1002ee28
  REFCNT = 1
  FLAGS = (NOK,pNOK)
  IV = 0
  NV = 0.15
  PV = 0x10025c10 "0.15"\0
  CUR = 4
  LEN = 5

文字列と数値の両方の値を持たせたいということ？