Question

In ruby I am parsing a date in the following format: 24092008. I want to convert each section (year, month, date) into a number.

I have split them up using a regex which produces three Strings which I am passing into the Integer constructor.

  date =~ /^([\d]{2})([\d]{2})([\d]{4})/   year = Integer($3)   month = Integer($2)   day = Integer($1) 

When it hits the month line it crashes as follows:

`Integer': invalid value for Integer: '09' (ArgumentError) 

It took me a while to realise that it’s interpreting the leading zero as Octal and 09 is not a valid Octal number (it works fine with ’07’).

Is there an elegant solution to this or should I just test for numbers less than 10 and remove the zero first?

Thanks.

Answer 1

I’m not familiar with regexes, so forgive me if this answer’s off-base. I’ve been assuming that $3, $2, and $1 are strings. Here’s what I did in IRB to replicate the problem:

irb(main):003:0> Integer('04') => 4 irb(main):004:0> Integer('09') ArgumentError: invalid value for Integer: '09'     from (irb):4:in `Integer'     from (irb):4     from :0 

But it looks like .to_i doesn’t have the same issues:

irb(main):005:0> '04'.to_i => 4 irb(main):006:0> '09'.to_i => 9