$ nodebrew use
Use of uninitialized value $version in pattern match (m//) at ./nodebrew line 331.
Use of uninitialized value $version in string eq at ./nodebrew line 353.
Use of uninitialized value $version in pattern match (m//) at ./nodebrew line 356.
Use of uninitialized value $orig_version in concatenation (.) or string at ./nodebrew line 71.
is not installed
This shoud show simple error message.