| class Range |
| ## |
| # call-seq: |
| # rng.first -> obj |
| # rng.first(n) -> an_array |
| # |
| # Returns the first object in the range, or an array of the first +n+ |
| # elements. |
| # |
| # (10..20).first #=> 10 |
| # (10..20).first(3) #=> [10, 11, 12] |
| # |
| def first(*args) |
| return self.begin if args.empty? |
| |
| raise ArgumentError, "wrong number of arguments (given #{args.length}, expected 1)" unless args.length == 1 |
| nv = args[0] |
| raise TypeError, "no implicit conversion from nil to integer" if nv.nil? |
| raise TypeError, "no implicit conversion of #{nv.class} into Integer" unless nv.respond_to?(:to_int) |
| n = nv.to_int |
| raise TypeError, "no implicit conversion of #{nv.class} into Integer" unless n.kind_of?(Integer) |
| raise ArgumentError, "negative array size (or size too big)" unless 0 <= n |
| ary = [] |
| each do |i| |
| break if n <= 0 |
| ary.push(i) |
| n -= 1 |
| end |
| ary |
| end |
| end |