Class Array
In: lib/core/facets/blank.rb
lib/core/facets/boolean.rb
lib/core/facets/kernel/object_state.rb
lib/core/facets/to_hash.rb
lib/core/facets/string/contains.rb
lib/core/facets/array/delete_values.rb
lib/core/facets/array/indexable.rb
lib/core/facets/array/rotate.rb
lib/core/facets/array/select.rb
lib/core/facets/array/combination.rb
lib/core/facets/array/conjoin.rb
lib/core/facets/array/recursively.rb
lib/core/facets/array/splice.rb
lib/core/facets/array/pad.rb
lib/core/facets/array/index.rb
lib/core/facets/array/permutation.rb
lib/core/facets/array/delete_unless.rb
lib/core/facets/array/product.rb
lib/core/facets/array/not_empty.rb
lib/core/facets/array/stackable.rb
lib/core/facets/array/merge.rb
lib/core/facets/array/only.rb
lib/core/facets/array/traverse.rb
Parent: Object

Methods

Included Modules

Indexable Stackable

External Aliases

empty? -> blank?
include? -> contains?
  Alias for include?.
shift -> first!
  Alias for shift, which removes and returns the first element in an array.
  a = ["a","y","z"]
  a.first!      #=> "a"
  p a           #=> ["y","z"]

CREDIT: Trans

pop -> last!
  Alias for pop, which removes and returns the last element in an array.
  a = [1,2]
  a.last! 3
  p a           #=> [1,2,3]

CREDIT: Trans

[]= -> store
  Store a value at a givne index. Store is an alias for #[]=.
unshift -> poke
  "Put On Top". This is an alias for unshift which puts an object# on top of the stack. It is the converse of push.
  a=[1,2,3]
  a.poke(9)   #=> [9,1,2,3]
  a           #=> [9,1,2,3]

CREDIT: Trans

shift -> pull
  Alias for shift which removes an object off first slot of an array. This is the contrary of pop.
  a=[1,2,3]
  a.pull  #=> 1
  a       #=> [2,3]

CREDIT: Trans

| -> merge
  Alias for |.
  [1,2].merge [2,3]  #=> [1,2,3]

Public Instance methods

**(*enums)

Alias for product

Yields the block to each unique combination of n elements.

  a = %w|a b c d|
  a.combination(3)

produces

  [["a", "b", "c"],
   ["a", "b", "d"],
   ["a", "c", "d"],
   ["b", "c", "d"]]

CREDIT: Florian Gross

[Source]

    # File lib/core/facets/array/combination.rb, line 21
21:     def combination(k=2)
22:       if block_given?
23:         s = to_a
24:         n = s.size
25:         return unless (1..n) === k
26:         idx = (0...k).to_a
27:         loop do
28:           yield s.values_at(*idx)
29:           i = k - 1
30:           i -= 1 while idx[i] == n - k + i
31:           break if i < 0
32:           idx[i] += 1
33:           (i + 1 ... k).each {|j| idx[j] = idx[i] + j - i}
34:         end
35:       else
36:         to_enum(:combination, k)
37:       end
38:     end

This is more advnaced form of join. It allows for fine control of separators.

NOTE: The old version used to default it‘s separator to ", " and default the terminating separator to " and ". This is no longer the case. You must specifically provide these parameters.

  [1,2,3].conjoin
  => "123"

  [1,2,3].conjoin(', ', ' and ')
  => "1, 2 and 3

  [1,2,3].conjoin(', ', :last => ' or ')
  => "1, 2 or 3

  [1,2,3].conjoin('; ', -1 => ' & ')
  => "1; 2 & 3

  [1,2,3,4].conjoin{ |i, a, b| i % 2 == 0 ? '.' : '-' }
  => "1.2-3.4"

  [1,1,2,2].conjoin{ |i, a, b| a == b ? '=' : '!=' }
  => "1=1!=2=2"

CREDIT: Trans

[Source]

    # File lib/core/facets/array/conjoin.rb, line 30
30:   def conjoin(*args, &block)
31:     return first.to_s if size < 2
32: 
33:     sep = []
34: 
35:     if block_given?
36:       (size - 1).times do |i|
37:         sep << yield(i, *slice(i,2))
38:       end
39:     else
40:       options   = (Hash===args.last) ? args.pop : {}
41:       separator = args.shift || ""
42:       options[-1] = args.shift unless args.empty?
43: 
44:       sep = [separator] * (size - 1)
45: 
46:       if options.key?(:last)
47:         options[-1] = options.delete(:last)
48:       end
49: 
50:       options[-1] ||= " and "
51: 
52:       options.each{|i, s| sep[i] = s}
53:     end
54:     zip(sep).join
55:   end

Inverse of delete_if.

  [1,2,3].delete_unless{ |x| x < 2 }
  => [1,2]

CREDIT: Daniel Schierbeck

[Source]

    # File lib/core/facets/array/delete_unless.rb, line 10
10:   def delete_unless(&block)
11:     delete_if { |element| not block.call(element) }
12:   end

Delete multiple values from array.

  a = [1,2,3,4]
  a.delete_values(1,2)   #=> [1,2]
  a                      #=> [3,4]

CREDIT: Trans

[Source]

    # File lib/core/facets/array/delete_values.rb, line 11
11:   def delete_values(*values)
12:     d = []
13:     values.each{ |v| d << delete(v) }
14:     d
15:   end

Delete multiple values from array given indexes or index range.

  a = [1,2,3,4]
  a.delete_values_at(1,2)   #=> [2,3]
  a                         #=> [1,4]
  a = [1,2,3,4]
  a.delete_values_at(0..2)  #=> [1,2,3]
  a                         #=> [4]

NOTE: It would be nice to see delete_at incorporate this funcitonaility.

CREDIT: Trans

[Source]

    # File lib/core/facets/array/delete_values.rb, line 32
32:   def delete_values_at(*selectors)
33:     idx = []
34:     selectors.each{ |i|
35:       case i
36:       when Range
37:         idx.concat( i.to_a )
38:       else
39:         idx << i.to_i
40:       end
41:     }
42:     idx.uniq!
43:     dvals = values_at(*idx)
44:     idx = (0...size).to_a - idx
45:     self.replace( values_at(*idx) )
46:     return dvals
47:   end

Allows index to accept a block.

OVERRIDE! This is one of the bery few core overrides in Facets.

[Source]

    # File lib/core/facets/array/index.rb, line 14
14:     def index(obj=nil, &block)
15:       if block_given?
16:         _facets_index(find(&block))
17:       else
18:         _facets_index(obj)
19:       end
20:     end

In place merge.

  a = [1,2]
  a.merge! [2,3]
  a => [1,2,3]

CREDIT: Trans

[Source]

    # File lib/core/facets/array/merge.rb, line 11
11:   def merge!( other )
12:     self.replace(self.merge(other))
13:   end

Not empty?

  [].not_empty?     #=> false
  [1,2].not_empty?  #=> true

[Source]

    # File lib/core/facets/array/not_empty.rb, line 8
 8:   def not_empty?
 9:     !empty?
10:   end

[Source]

    # File lib/core/facets/kernel/object_state.rb, line 29
29:   def object_state(data=nil)
30:     data ? replace(data) : dup
31:   end

Returns the only element in the array. Raises an IndexError if the array‘s size is not 1.

  [5].only      # -> 5
  [1,2,3].only  # -> IndexError
  [].only       # -> IndexError

CREDIT: Gavin Sinclair, Noah Gibbs

[Source]

    # File lib/core/facets/array/only.rb, line 12
12:   def only
13:     unless size == 1
14:       raise IndexError, "Array#only called on non-single-element array"
15:     end
16:     first
17:   end

Pad an array with a given value upto a given length.

  [0,1,2].pad(6,"a")  #=> [0,1,2,"a","a","a"]

If length is a negative number padding will be added to the beginning of the array.

  [0,1,2].pad(-6,"a")  #=> ["a","a","a",0,1,2]

CREDIT: Richard Laugesen

[Source]

    # File lib/core/facets/array/pad.rb, line 14
14:   def pad(len, val=nil)
15:     return dup if self.size >= len.abs
16:     if len < 0
17:       Array.new((len+size).abs,val) + self
18:     else
19:       self + Array.new(len-size,val)
20:     end
21:   end

Like pad but changes the array in place.

   a = [0,1,2]
   a.pad!(6,"x")
   a  #=> [0,1,2,"x","x","x"]

CREDIT: Richard Laugesen

[Source]

    # File lib/core/facets/array/pad.rb, line 31
31:   def pad!(len, val=nil)
32:     return self if self.size >= len.abs
33:     if len < 0
34:       replace Array.new((len+size).abs,val) + self
35:     else
36:       concat Array.new(len-size,val)
37:     end
38:   end

Permutation provids the possible orders of an enumerable. Each is indexed by a permutation number. The maximum number of arrangements is the factorial of the size of the array.

CREDIT: Shin-ichiro Hara

[Source]

    # File lib/core/facets/array/permutation.rb, line 11
11:     def permutation(n=size)
12:       if size < n or n < 0
13:       elsif n == 0
14:         yield([])
15:       else
16:         self[1..-1].permutation(n - 1) do |x|
17:           (0...n).each do |i|
18:             yield(x[0...i] + [first] + x[i..-1])
19:           end
20:         end
21:         self[1..-1].permutation(n) do |x|
22:           yield(x)
23:         end
24:       end
25:     end

Provides the cartesian product of two or more arrays.

  a = []
  [1,2].product([4,5])
  a  #=> [[1, 4],[1, 5],[2, 4],[2, 5]]

CREDIT: Thomas Hafner

[Source]

    # File lib/core/facets/array/product.rb, line 13
13:     def product(*enums)
14:       enums.unshift self
15:       result = [[]]
16:       while [] != enums
17:         t, result = result, []
18:         b, *enums = enums
19:         t.each do |a|
20:           b.each do |n|
21:             result << a + [n]
22:           end
23:         end
24:       end
25:       result
26:     end

Apply a block to hash, and recursively apply that block to each subhash.

  arr = ["a", ["b", "c", nil], nil]
  arr.recursively{|a| a.compact! }
  => ["a", ["b", "c"]]

TODO: Can this be generalized in Enumerbale?

[Source]

    # File lib/core/facets/array/recursively.rb, line 12
12:   def recursively(&block)
13:     a = inject([]) do |array, value|
14:       if value.is_a?(Array)
15:         array << value.recursively(&block)
16:       else
17:         array << value
18:       end
19:       array
20:     end
21:     yield a
22:   end

In place form of recursively.

[Source]

    # File lib/core/facets/array/recursively.rb, line 26
26:   def recursively!(&block)
27:     replace(recursively(&block))
28:   end

Rotates an array‘s elements from back to front n times.

  [1,2,3].rotate      #=> [3,1,2]
  [3,1,2].rotate      #=> [2,3,1]
  [3,1,2].rotate      #=> [1,2,3]
  [1,2,3].rotate(3)   #=> [1,2,3]

A negative parameter reverses the order from front to back.

  [1,2,3].rotate(-1)  #=> [2,3,1]

CREDIT: Florian Gross, Thomas Sawyer

[Source]

    # File lib/core/facets/array/rotate.rb, line 16
16:   def rotate(n=1)
17:     self.dup.rotate!(n)
18:   end

Same as rotate, but acts in place.

  a = [1,2,3]
  a.rotate!
  a  #=> [3,1,2]

CREDIT: Florian Gross, Thomas Sawyer

[Source]

    # File lib/core/facets/array/rotate.rb, line 28
28:   def rotate!(n=1)
29:     n = n.to_int
30:     return self if (n == 0 or self.empty?)
31:     if n > 0
32:       n.abs.times{ self.unshift( self.pop ) }
33:     else
34:       n.abs.times{ self.push( self.shift ) }
35:     end
36:     self
37:   end

As with select but modifies the Array in place.

  a = [1,2,3,4,5,6,7,8,9,10]
  a.select!{ |e| e % 2 == 0 }
  a  #=> [2,4,6,8,10]

CREDIT: Gavin Sinclair

[Source]

    # File lib/core/facets/array/select.rb, line 11
11:   def select!  # :yield:
12:     reject!{ |e| not yield(e) }
13:   end

Splice acts a combination of slice! and store. If two arguments are given it calls store. If a single argument is give it calls slice!.

  a = [1,2,3]
  a.splice(1)    #=> 2
  a              #=> [1,3]

  a = [1,2,3]
  a.splice(1,4)  #=> 4
  a              #=>[1,4,3]

CREDIT: Trans

[Source]

    # File lib/core/facets/array/splice.rb, line 17
17:   def splice(*args)
18:     if args.size == 1
19:       slice!(*args)
20:     else
21:       store(*args)
22:     end
23:   end

Boolean conversion for not empty?

[Source]

    # File lib/core/facets/boolean.rb, line 60
60:   def to_b
61:     ! self.empty?
62:   end

Converts an array into a hash. Converting an array into a hash is not a one-to-one conversion, for this reason to_h examines at the array being converted and then dispatches the conversion to the most sutiable specialized function. There are three possiblities for this.

If the array is a collection of perfect pairs, like that which Hash#to_a generates, then conversion is handled by to_h_flat.

  a = [ [:a,1], [:b,2] ]
  a.to_h  #=> { :a=>1, :b=>2 }

If the array contains only arrays, but are not perfect pairs, then to_h_multi is called.

  a = [ [:a,1,2], [:b,2], [:c], [:d] ]
  a.to_h  #=> { :a=>[1,2], :b=>[2], :c=>[], :d=>[] }

If the array contians objects other then arrays then the to_h_splat method is called.

  a = [ [:a,1,2], 2, :b, [:c,3], 9 ]
  a.to_h  #=> { [:a,1,2]=>2, :b=>[:c,3], 9=>nil }

Finally, a particular dispatch can be forced by specifying the mode of conversion, eg. +:multi+, +:splat+, +:flat+, +:assoc+, etc.

Setting mode to true is the same as setting it +:multi+. This has been left in for backward compatability.

NOTE: The use of a values parameter has been deprecated because that functionality is as simple as:

  array1.zip(array2).to_h

CREDIT: Robert Klemme CREDIT: Trans

[Source]

    # File lib/core/facets/to_hash.rb, line 52
52:   def to_h(mode=nil)
53:     case mode
54:     when :splat
55:       return to_h_splat
56:     when :flat
57:       return to_h_flat
58:     when :multi, true
59:       return to_h_multi
60:     when :assoc
61:       return to_h_assoc
62:     else
63:       return to_h_auto
64:     end
65:   end

When a mixed or multi-element accociative array is used, the result is as follows:

  a = [ [:a,1,2], [:b,2], [:c], :d ]
  a.to_h  #=> { :a=>[1,2], :b=>[2], :c=>[], :d=>[] }

If the first entry of any subelements are the same, then the value will be set to the last occuring value.

  a = [ :x, [:x], [:x,1,2], [:x,3], [:x,4] ]
  a.to_h_assoc  #=> { :x=>4 }

[Source]

     # File lib/core/facets/to_hash.rb, line 156
156:   def to_h_assoc
157:     h = {}
158:     each do |k,*v| 
159:       h[k] = v
160:     end
161:     h
162:   end

Converts an array into a hash. Converting an array into a hash is not a one-to-one conversion, for this reason to_h examines at the array being converted and then dispatches the conversion to the most sutiable specialized function. There are three possiblities for this.

If the array is a collection of perfect pairs, like that which Hash#to_a generates, then conversion is handled by to_h_flat.

  a = [ [:a,1], [:b,2] ]
  a.to_h  #=> { :a=>1, :b=>2 }

If the array contains only arrays, but are not perfect pairs, then to_h_multi is called.

  a = [ [:a,1,2], [:b,2], [:c], [:d] ]
  a.to_h  #=> { :a=>[1,2], :b=>[2], :c=>[], :d=>[] }

If the array contians objects other then arrays then the to_h_splat method is called.

  a = [ [:a,1,2], 2, :b, [:c,3], 9 ]
  a.to_h  #=> { [:a,1,2]=>2, :b=>[:c,3], 9=>nil }

[Source]

     # File lib/core/facets/to_hash.rb, line 92
 92:   def to_h_auto
 93:     pairs = true
 94:     mixed = false
 95: 
 96:     each do |e|
 97:       case e
 98:       when Array
 99:         pairs = false if e.size > 2
100:       else
101:         mixed = true
102:       end
103:     end
104: 
105:     if mixed
106:       to_h_splat
107:     elsif pairs
108:       to_h_flat
109:     else
110:       to_h_multi
111:     end
112:   end

This is equivalent to Hash, but it will pad the array with a nil object if there are not an even number of elements.

  a = [:a,1,[:b,2,:c]]
  a.to_h_flat  #=> { :a=>1, :b=>2, :c=>nil }

[Source]

     # File lib/core/facets/to_hash.rb, line 134
134:   def to_h_flat
135:     a = flatten
136:     a << nil if a.size % 2 == 1
137:     Hash[*a]
138:   end

When a mixed or multi-element accociative array is used, the result is as follows:

  a = [ [:a,1,2], [:b,2], [:c], :d ]
  a.to_h  #=> { :a=>[1,2], :b=>[2], :c=>[], :d=>[] }

If the first entry of the subelements is the same, then the values will be merged using concat.

  a = [ [:a,1,2], [:a,3], [:a,4], [:a], :a ]
  a.to_h_multi  #=> { :a=>[1,2,3,4] }

[Source]

     # File lib/core/facets/to_hash.rb, line 176
176:   def to_h_multi
177:     h = {}
178:     each do |k,*v| 
179:       h[k] ||= []
180:       h[k].concat(v)
181:     end
182:     h
183:   end

This is equivalent to Hash[*array], but it will pad the array with a nil object if there are not an even number of elements.

  a = [:a,1,:b,2,:c]
  a.to_h_splat  #=> { :a=>1, :b=>2, :c=>nil }

[Source]

     # File lib/core/facets/to_hash.rb, line 121
121:   def to_h_splat
122:     a = dup
123:     a << nil if a.size % 2 == 1
124:     Hash[*a]
125:   end

[Source]

    # File lib/core/facets/array/traverse.rb, line 5
 5:   def traverse(&block)
 6:     map do |item|
 7:       if item.is_a?(self.class)
 8:         item.traverse(&block)
 9:       else
10:         yield item
11:       end
12:     end
13:   end

[Source]

    # File lib/core/facets/array/traverse.rb, line 17
17:   def traverse!(&block)
18:     replace(traverse(&block))
19:   end

[Validate]