diff options
Diffstat (limited to 'mrbgems/mruby-enum-ext')
| -rw-r--r-- | mrbgems/mruby-enum-ext/mrblib/enum.rb | 30 | ||||
| -rw-r--r-- | mrbgems/mruby-enum-ext/test/enum.rb | 8 |
2 files changed, 38 insertions, 0 deletions
diff --git a/mrbgems/mruby-enum-ext/mrblib/enum.rb b/mrbgems/mruby-enum-ext/mrblib/enum.rb index b427bd67e..178496e7e 100644 --- a/mrbgems/mruby-enum-ext/mrblib/enum.rb +++ b/mrbgems/mruby-enum-ext/mrblib/enum.rb @@ -826,4 +826,34 @@ module Enumerable end hash.values end + + def filter_map(&blk) + return to_enum(:find_index, val) unless blk + + ary = [] + self.each do |x| + x = blk.call(x) + ary.push x if x + end + ary + end + + alias filter select + + ## + # call-seq: + # enum.tally -> a_hash + # + # Tallys the collection. Returns a hash where the keys are the + # elements and the values are numbers of elements in the collection + # that correspond to the key. + # + # ["a", "b", "c", "b"].tally #=> {"a"=>1, "b"=>2, "c"=>1} + def tally + hash = {} + self.each do |x| + hash[x] = (hash[x]||0)+1 + end + hash + end end diff --git a/mrbgems/mruby-enum-ext/test/enum.rb b/mrbgems/mruby-enum-ext/test/enum.rb index 6929d8ddc..f0301a2d9 100644 --- a/mrbgems/mruby-enum-ext/test/enum.rb +++ b/mrbgems/mruby-enum-ext/test/enum.rb @@ -188,3 +188,11 @@ assert("Enumerable#to_h") do assert_equal h0, h assert_equal({1=>4,3=>8}, c.new.to_h{|k,v|[k,v*2]}) end + +assert("Enumerable#filter_map") do + assert_equal [4, 8, 12, 16, 20], (1..10).filter_map{|i| i * 2 if i%2==0} +end + +assert("Enumerable#tally") do + assert_equal({"a"=>1, "b"=>2, "c"=>1}, ["a", "b", "c", "b"].tally) +end |
