Class: Bychar::ReaderStrbuf

Inherits:
Object
  • Object
show all
Defined in:
lib/impls/reader_strbuf.rb

Overview

A String-bassed intermediary buffer. We will only use it on 1.9 but we keep it compatible with 1.8 so that we can benchmark both

Instance Method Summary collapse

Constructor Details

#initialize(with_io) ⇒ ReaderStrbuf

:nodoc: :all



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# File 'lib/impls/reader_strbuf.rb', line 6

def initialize(with_io)
  @io = with_io
  @pos_in_buf = 1
  @maximum_pos = 0
  @buf = ''
  @oneeight = RUBY_VERSION < "1.9"
end

Instance Method Details

#read_one_char ⇒ Object

Will transparently read one byte off the contained IO, maintaining the internal cache. If the cache has been depleted it will read a big chunk from the IO and cache it and then return the byte



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# File 'lib/impls/reader_strbuf.rb', line 17

def read_one_char
  if @pos_in_buf > @maximum_pos
    @buf = @io.read(DEFAULT_BUFFER_SIZE)
    
    return nil if @buf.nil?
  
    @maximum_pos = @buf.length - 1
    @pos_in_buf = 0
  end

  char_i = @pos_in_buf
  @pos_in_buf += 1
  
  # For Ruby 1.8 calling Numeric#chr is faster than allocating a Range for String#slice
  @oneeight ? @buf[char_i].chr : @buf[char_i]
end