diff options
| -rw-r--r-- | mrbgems/mruby-enum-ext/mrblib/enum.rb | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/mrbgems/mruby-enum-ext/mrblib/enum.rb b/mrbgems/mruby-enum-ext/mrblib/enum.rb index f250d39f1..85779ee59 100644 --- a/mrbgems/mruby-enum-ext/mrblib/enum.rb +++ b/mrbgems/mruby-enum-ext/mrblib/enum.rb @@ -161,4 +161,30 @@ module Enumerable h end + NONE = Object.new + ## + # call-seq: + # enum.first -> obj or nil + # enum.first(n) -> an_array + # + # Returns the first element, or the first +n+ elements, of the enumerable. + # If the enumerable is empty, the first form returns <code>nil</code>, and the + # second form returns an empty array. + def first(n=NONE) + if n == NONE + self.each do |e| + return e + end + return nil + else + a = [] + i = 0 + self.each do |e| + break if n<=i + a.push e + i += 1 + end + a + end + end end |