Class: Hana::Pointer

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/hana.rb

Defined Under Namespace

Classes: Exception, FormatError

Constant Summary collapse

ESC =

:nodoc:

{'^/' => '/', '^^' => '^', '~0' => '~', '~1' => '/'}

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(path) ⇒ Pointer

Returns a new instance of Pointer.



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# File 'lib/hana.rb', line 15

def initialize path
  @path = Pointer.parse path
end

Class Method Details

.eval(list, object) ⇒ Object 



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# File 'lib/hana.rb', line 27

def self.eval list, object
  list.inject(object) { |o, part|
    return nil unless o

    if Array === o
      raise Patch::IndexError unless part =~ /\A(?:\d|[1-9]\d+)\Z/
      part = part.to_i
    end
    o[part]
  }
end

.parse(path) ⇒ Object 



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# File 'lib/hana.rb', line 39

def self.parse path
  return [''] if path == '/'
  return []   if path == ''

  unless path.start_with? '/'
    raise FormatError, "JSON Pointer should start with a slash"
  end

  parts = path.sub(/^\//, '').split(/(?<!\^)\//).each { |part|
    part.gsub!(/\^[\/^]|~[01]/) { |m| ESC[m] }
  }

  parts.push("") if path[-1] == '/'
  parts
end

Instance Method Details

#each(&block) ⇒ Object 



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# File 'lib/hana.rb', line 19

def each(&block); @path.each(&block); end

#eval(object) ⇒ Object 



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# File 'lib/hana.rb', line 21

def eval object
  Pointer.eval @path, object
end