Class: PDF::Core::FilterList

Inherits:
Object
  • Object
show all
Defined in:
lib/pdf/core/filter_list.rb

Overview

A representation of a list of filters applied to a stream.

Defined Under Namespace

Classes: NotFilter

Instance Method Summary collapse

Constructor Details

#initialize ⇒ FilterList

Returns a new instance of FilterList.

Source Code
lib/pdf/core/filter_list.rb, line 25
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def initialize

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  @list = []

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end

Instance Method Details

#<<(filter) ⇒ self

Appends a filter to the list

Parameters:

  • filter (Symbol, Hash) —

    a filter to append

Returns:

  • (self)

Raises:

Source Code
lib/pdf/core/filter_list.rb, line 34
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def <<(filter)

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  case filter

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  when Symbol

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    @list << [filter, nil]

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  when ::Hash

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    filter.each do |name, params|

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      @list << [name, params]

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    end

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  else

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    raise NotFilter.new(filter: filter)

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  end

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  self

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end







    
      

  

  
    #decode_params  ⇒ Array<[Hash, nil]> 
  

  

  


  

    
Parameters of filters



  





  


Returns:


    
  
    
  • 
      
      
        (Array<[Hash, nil]>)
      
      
      
    
    • 
  







  Source Code
  
lib/pdf/core/filter_list.rb, line 69

  
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def decode_params

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  @list.map do |(_, params)|

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    params

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  end

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end







    
      

  

  
    #each {|(name, decode_params)| ... } ⇒ Array<Array<(Symbol, [Hash, nil])>> 
  

  

  


  

    
Iterates over filters



  





  


Yields:


    
  
    
  • 
      
      
        ((name, decode_params))
      
      
      
        —
        
    an array of filter name and decode
parameters
    

    
      
    
    • 
  



Yield Parameters:


    
  
    
  • 
      
        name
      
      
        (Symbol)
      
      
      
        —
        
    filter name
    

    
      
    
    • 
  
    
  • 
      
        decode_params
      
      
        (Hash, nil)
      
      
      
        —
        
    decode params
    

    
      
    
    • 
  



Returns:


    
  
    
  • 
      
      
        (Array<Array<(Symbol, [Hash, nil])>>)
      
      
      
        —
        
    normalized filter list
    

    
      
    
    • 
  







  Source Code
  
lib/pdf/core/filter_list.rb, line 87

  
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def each(&block)

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  @list.each(&block)

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end







    
      

  

  
    #inspect  ⇒ String 
  

  

  


  

    


  





  


Returns:


    
  
    
  • 
      
      
        (String)
      
      
      
    
    • 
  







  Source Code
  
lib/pdf/core/filter_list.rb, line 76

  
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def inspect

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  @list.inspect

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end







    
      

  

  
    #names  ⇒ Array<Symbol> 
  

  

  


  

    
Names of filters in the list



  





  


Returns:


    
  
    
  • 
      
      
        (Array<Symbol>)
      
      
      
    
    • 
  







  Source Code
  
lib/pdf/core/filter_list.rb, line 60

  
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def names

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  @list.map do |(name, _)|

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    name

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  end

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end







    
      

  

  
    #normalized  ⇒ Array<Array<(Symbol, [Hash, nil])>> 
  

  
    Also known as:
    to_a
    
  

  


  

    
A normalized representation of the filter list



  





  


Returns:


    
  
    
  • 
      
      
        (Array<Array<(Symbol, [Hash, nil])>>)
      
      
      
    
    • 
  







  Source Code
  
lib/pdf/core/filter_list.rb, line 52

  
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def normalized

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  @list

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end