pi@raspberrypi:~ $ cpan Number::Format
Reading '/home/pi/.cpan/Metadata'
  Database was generated on Wed, 07 Feb 2018 12:41:02 GMT
Running install for module 'Number::Format'
Checksum for /home/pi/.cpan/sources/authors/id/W/WR/WRW/Number-Format-1.75.tar.gz ok
Uncompressed /home/pi/.cpan/sources/authors/id/W/WR/WRW/Number-Format-1.75.tar.gz successfully
Using Tar:/bin/tar xf "Number-Format-1.75.tar":
Couldn't untar Number-Format-1.75.tar: 'Cannot allocate memory'
'YAML' not installed, will not store persistent state
  WRW/Number-Format-1.75.tar.gz
  Had problems unarchiving. Please build manually