New DateTime instead of String in ruby

Assuming your string is in the correct format, then you’re probably looking for:

@date_of_birth = array[0].to_datetime
@date_of_death = array[1].to_datetime

See here for more info:

https://apidock.com/rails/String/to_datetime

This:

DateTime.new(1979,1,1) DateTime.new(2012,3,29)

Is not code. What do you expect that to do?

If you want two DateTimes as a space-separated string, do something like:

"#{DateTime.new(1979,1,1)} #{DateTime.new(2012,3,29)}" 

When you have something like #{...} inside a set of double quotation marks (they must be double, not single quotation marks), it’s called string interpolation. Learn it. Love it. Live it.

But, for the life of me, I don’t know why you wouldn’t do:

[DateTime.new(1979,1,1), DateTime.new(2012,3,29)]

Which gives you an array, so no split needed. Just:

def split_line
  @date_of_birth = array[0] 
  @date_of_death = array[1] 
end

If you want DateTime values, grab the numbers and create them:

require 'date'

'DateTime.new(1979,1,1) DateTime.new(2012,3,29)'.split.map { |s|
  DateTime.new(*s.scan(/d+/).map(&:to_i) )
}
# => [#<DateTime: 1979-01-01T00:00:00+00:00 ((2443875j,0s,0n),+0s,2299161j)>,
#     #<DateTime: 2012-03-29T00:00:00+00:00 ((2456016j,0s,0n),+0s,2299161j)>]

The values aren’t DateTime though, they’re Dates:

'DateTime.new(1979,1,1) DateTime.new(2012,3,29)'.split.map { |s|
  Date.new(*s.scan(/d+/).map(&:to_i) )
}
# => [#<Date: 1979-01-01 ((2443875j,0s,0n),+0s,2299161j)>,
#     #<Date: 2012-03-29 ((2456016j,0s,0n),+0s,2299161j)>]

Breaking it down:

'DateTime.new(1979,1,1) DateTime.new(2012,3,29)'.split # => ["DateTime.new(1979,1,1)", "DateTime.new(2012,3,29)"]
  .map { |s|
  Date.new(
    *s.scan(/d+/) # => ["1979", "1", "1"], ["2012", "3", "29"]
    .map(&:to_i) # => [1979, 1, 1],       [2012, 3, 29]
  )
}
# => [#<Date: 1979-01-01 ((2443875j,0s,0n),+0s,2299161j)>,
#     #<Date: 2012-03-29 ((2456016j,0s,0n),+0s,2299161j)>]

* (AKA “splat”), used like this, explodes an array into its elements, which is useful when you have an array but the method only takes separate parameters.

The bigger question is why you’re getting values like that in a text file.