my $self = shift;
	my ($amount) = @_;
    my $amountOld = $self->amountAccount;
    my $amountNew = $amountOld + $amount;
    $self->amountAccount($amountNew);
    if(length($amountOld) < 8 && length($amountNew) >= 8) {
        use Devel::Peek;    
        print("\n\n"), Dump($amountOld), Dump($amount), Dump($amountNew), print("Went bad here: ($amountOld + $amount = $amountNew)\n\n");
        $amount = 0.9;
        $amountOld = 4253.95;
        $amountNew = $amountOld + $amount;
        print("\nNew values\n"), Dump($amountOld), Dump($amount), Dump($amountNew), print("Correct output: ($amountOld + $amount = $amountNew)\n\n");
    }

##</code><code>##

SV = PVNV(0x2c8ef8c) at 0x23b4958
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,NOK,POK,pNOK,pPOK)
  IV = 4256
  NV = 4253.95
  PV = 0x2d179a4 "4253.95"\0
  CUR = 7
  LEN = 35
SV = PVNV(0x2c8ef44) at 0x23b4928
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,NOK,pIOK,pNOK)
  IV = 0
  NV = 0.9
  PV = 0
SV = PVNV(0x2c8efa4) at 0x23b4988
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,NOK,POK,pNOK,pPOK)
  IV = 4309
  NV = 4254.84999999999
  PV = 0x2d17d9c "4254.84999999999"\0
  CUR = 16
  LEN = 35
Went bad here: (4253.95 + 0.9 = 4254.84999999999)


New values
SV = PVNV(0x2c8ef8c) at 0x23b4958
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,NOK,pNOK)
  IV = 4256
  NV = 4253.95
  PV = 0x2d179a4 "4253.95"\0
  CUR = 7
  LEN = 35
SV = PVNV(0x2c8ef44) at 0x23b4928
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,NOK,pIOK,pNOK)
  IV = 0
  NV = 0.9
  PV = 0x2dfa064 "0.9"\0
  CUR = 3
  LEN = 35
SV = PVNV(0x2c8efa4) at 0x23b4988
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,NOK,pNOK)
  IV = 4309
  NV = 4254.85
  PV = 0x2d17d9c "4254.84999999999"\0
  CUR = 16
  LEN = 35
Correct output: (4253.95 + 0.9 = 4254.85)
##</code><code>##

perl -v

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(with 8 registered patches, see perl -V for more detail)