Class: Readline::History

Inherits:
Object
  • Object
show all
Extended by:
Enumerable
Defined in:
lib/readline.rb

Overview

The History class encapsulates a history of all commands entered by users at the prompt, providing an interface for inspection and retrieval of all commands.

Class Method Summary collapse

Class Method Details

.<<(str) ⇒ Object

Synonym for Readline.add_history.



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# File 'lib/readline.rb', line 338

def self.<<(str)
   RbReadline.add_history(str)
end

.[](index) ⇒ Object

Returns the command that was entered at the specified index in the history buffer.

Raises an IndexError if the entry is nil.



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# File 'lib/readline.rb', line 309

def self.[](index)
   if index < 0
      index += RbReadline.history_length
   end
   entry = RbReadline.history_get(RbReadline.history_base+index)
   if entry.nil?
      raise IndexError,"invalid index"
   end
   entry.line.dup
end

.[]=(index, str) ⇒ Object

Sets the command str at the given index in the history buffer.

You can only replace an existing entry. Attempting to create a new entry will result in an IndexError.



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# File 'lib/readline.rb', line 325

def self.[]=(index,str)
   if index<0
      index += RbReadline.history_length
   end
   entry = RbReadline.replace_history_entry(index,str,nil)
   if entry.nil?
      raise IndexError,"invalid index"
   end
   str
end

.delete_at(index) ⇒ Object

Deletes an entry from the histoyr buffer at the specified index.



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# File 'lib/readline.rb', line 417

def self.delete_at(index)
   if index < 0
      i += RbReadline.history_length
   end
   if index < 0 || index > RbReadline.history_length - 1
      raise IndexError, "invalid index"
   end
   rb_remove_history(index)
end

.each ⇒ Object

Iterates over each entry in the history buffer.



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# File 'lib/readline.rb', line 387

def self.each()
   for i in 0 ... RbReadline.history_length
      entry = RbReadline.history_get(RbReadline.history_base + i)
      break if entry.nil?
      yield entry.line.dup
   end
   self
end

.empty? ⇒ Boolean

Returns a bolean value indicating whether or not the history buffer is empty.

Returns:

  • (Boolean) 


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# File 'lib/readline.rb', line 411

def self.empty?()
   RbReadline.history_length == 0
end

.length ⇒ Object

Returns the length of the history buffer.



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# File 'lib/readline.rb', line 398

def self.length()
   RbReadline.history_length
end

.pop ⇒ Object

Removes and returns the last element from the history buffer.



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# File 'lib/readline.rb', line 367

def self.pop()
   if RbReadline.history_length>0
      rb_remove_history(RbReadline.history_length-1)
   else
      nil
   end
end

.push(*args) ⇒ Object

Pushes a list of args onto the history buffer.



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# File 'lib/readline.rb', line 344

def self.push(*args)
   args.each do |str|
      RbReadline.add_history(str)
   end
end

.rb_remove_history(index) ⇒ Object

Internal function that removes the item at index from the history buffer, performing necessary duplication in the process. – TODO: mark private?



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# File 'lib/readline.rb', line 355

def self.rb_remove_history(index)
   entry = RbReadline.remove_history(index)
   if (entry)
      val = entry.line.dup
      entry = nil
      return val
   end
   nil
end

.shift ⇒ Object

Removes and returns the first element from the history buffer.



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# File 'lib/readline.rb', line 377

def self.shift()
   if RbReadline.history_length>0
      rb_remove_history(0)
   else
      nil
   end
end

.size ⇒ Object

Synonym for Readline.length.



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# File 'lib/readline.rb', line 404

def self.size()
   RbReadline.history_length
end

.to_s ⇒ Object

The History class, stringified in all caps. – Why?



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# File 'lib/readline.rb', line 300

def self.to_s
   "HISTORY"
end