module Rack::Accept::Header::PublicInstanceMethods

A table of all values of this header to their respective quality factors (qvalues).

Determines if the given value is acceptable (does not have a qvalue of 0) according to this header.

# File lib/rack/accept/header.rb, line 97
def accept?(value)
  qvalue(value) != 0
end

A shortcut for retrieving the first result of sort.

# File lib/rack/accept/header.rb, line 135
def best_of(values, keep_unacceptables=false)
  sort(values, keep_unacceptables).first
end

The name of this header. Should be overridden in classes that mixin this module.

# File lib/rack/accept/header.rb, line 75
def name
  ''
end

Returns the quality factor (qvalue) of the given value. Should be overridden in classes that mixin this module.

# File lib/rack/accept/header.rb, line 81
def qvalue(value)
  1
end

Sorts the given values according to the qvalue of each while preserving the original order. See sort_with_qvalues for more information on exactly how the sort is performed.

# File lib/rack/accept/header.rb, line 130
def sort(values, keep_unacceptables=false)
  sort_with_qvalues(values, keep_unacceptables).map {|q, v| v }
end

Returns a copy of the given values array, sorted by quality factor (qvalue). Each element of the returned array is itself an array containing two objects: 1) the value’s qvalue and 2) the original value.

It is important to note that this sort is a “stable sort”. In other words, the order of the original values is preserved so long as the qvalue for each is the same. This expectation can be useful when trying to determine which of a variety of options has the highest qvalue. If the user prefers using one option over another (for any number of reasons), he should put it first in values. He may then use the first result with confidence that it is both most acceptable to the client and most convenient for him as well.

# File lib/rack/accept/header.rb, line 114
def sort_with_qvalues(values, keep_unacceptables=true)
  qvalues = {}
  values.each do |v|
    q = qvalue(v)
    if q != 0 || keep_unacceptables
      qvalues[q] ||= []
      qvalues[q] << v
    end
  end
  order = qvalues.keys.sort.reverse
  order.inject([]) {|m, q| m.concat(qvalues[q].map {|v| [q, v] }) }
end

Returns a string representation of this header.

# File lib/rack/accept/header.rb, line 140
def to_s
  [name, value].join(': ')
end

Returns the value of this header as a string.

# File lib/rack/accept/header.rb, line 86
def value
  join(@qvalues)
end

Returns an array of all values of this header, in no particular order.

# File lib/rack/accept/header.rb, line 91
def values
  @qvalues.keys
end