Class: LPS

Inherits:
Object
  • Object
show all
Includes:
OptionInitializer
Defined in:
lib/lps.rb,
lib/lps/version.rb

Constant Summary collapse

VERSION = 
'0.2.1'

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(opts = {}) ⇒ LPS

Returns a new instance of LPS.

Parameters:

  • opts (Hash) (defaults to: {}) —

    Options Hash.

Options Hash (opts):

  • :freq (Numeric) —

    Frequency of loop execution (loops/sec)

  • :cond (#call) —

    Loop condition

Raises:

  • (ArgumentError) 


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# File 'lib/lps.rb', line 81

def initialize opts = {}
  validate_options opts

  freq, intv, @while = opts.values_at :freq, :interval, :while
  raise ArgumentError,
    "can't have both frequency and interval" if freq && intv

  @freq =
    if freq
      freq
    elsif intv
      (intv == 0) ? nil : 1.0 / intv
    else
      nil
    end
  @interval = @freq ? 1.0 / @freq : 0
end

Instance Attribute Details

#freq ⇒ Number

Returns Loop frequency.

Returns:

  • (Number) —

    Loop frequency



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# File 'lib/lps.rb', line 8

class LPS
  include OptionInitializer
  option_initializer! :freq, :interval => Numeric, :while => :&
  option_validator :freq do |v|
    msg = 'frequency must be a positive number (or nil)'
    raise TypeError, msg unless v.is_a?(Numeric) || v.nil?
    raise ArgumentError, msg if v.is_a?(Numeric) && v <= 0
  end
  option_validator :interval do |v|
    raise ArgumentError, 'interval must be a non-negative number' if v < 0
  end

  attr_reader :freq, :interval

  # Main loop
  # @param [Proc] block Loop
  def loop &block
    ret = nil
    always = @while.nil?

    if @freq.nil?
      while always || @while.call
        ret = block.call self

        # Frequency set!
        return loop(&block) if @freq
      end
    else
      nt = Time.now
      while always || @while.call
        ret = block.call self

        # Frequency unset!
        return loop(&block) unless @freq

        nt   += @interval
        now   = Time.now
        diff  = nt - now

        if diff > 0.01
          sleep diff
        elsif diff < 0
          nt = now
        end
      end
    end
    ret
  end

  # Changes loop frequency
  # @param [Number|nil] f Loop frequency
  # @return [Number|nil]
  def freq= f
    validate_options(:freq => f)

    @freq, @interval = [f, f ? 1.0 / f : 0]
    @freq
  end

  # Changes loop interval
  # @param [Number] intv Loop interval
  # @return [Number]
  def interval= intv
    validate_options(:interval => intv)

    @freq, @interval = [(intv == 0) ? nil : 1.0 / intv, intv]
    @interval
  end

  # @param [Hash] opts Options Hash.
  # @option opts [Numeric] :freq Frequency of loop execution (loops/sec)
  # @option opts [#call] :cond Loop condition
  # @private
  def initialize opts = {}
    validate_options opts

    freq, intv, @while = opts.values_at :freq, :interval, :while
    raise ArgumentError,
      "can't have both frequency and interval" if freq && intv

    @freq =
      if freq
        freq
      elsif intv
        (intv == 0) ? nil : 1.0 / intv
      else
        nil
      end
    @interval = @freq ? 1.0 / @freq : 0
  end
end

#interval ⇒ Number

Returns Loop interval (inverse of frequency).

Returns:

  • (Number) —

    Loop interval (inverse of frequency)



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# File 'lib/lps.rb', line 8

class LPS
  include OptionInitializer
  option_initializer! :freq, :interval => Numeric, :while => :&
  option_validator :freq do |v|
    msg = 'frequency must be a positive number (or nil)'
    raise TypeError, msg unless v.is_a?(Numeric) || v.nil?
    raise ArgumentError, msg if v.is_a?(Numeric) && v <= 0
  end
  option_validator :interval do |v|
    raise ArgumentError, 'interval must be a non-negative number' if v < 0
  end

  attr_reader :freq, :interval

  # Main loop
  # @param [Proc] block Loop
  def loop &block
    ret = nil
    always = @while.nil?

    if @freq.nil?
      while always || @while.call
        ret = block.call self

        # Frequency set!
        return loop(&block) if @freq
      end
    else
      nt = Time.now
      while always || @while.call
        ret = block.call self

        # Frequency unset!
        return loop(&block) unless @freq

        nt   += @interval
        now   = Time.now
        diff  = nt - now

        if diff > 0.01
          sleep diff
        elsif diff < 0
          nt = now
        end
      end
    end
    ret
  end

  # Changes loop frequency
  # @param [Number|nil] f Loop frequency
  # @return [Number|nil]
  def freq= f
    validate_options(:freq => f)

    @freq, @interval = [f, f ? 1.0 / f : 0]
    @freq
  end

  # Changes loop interval
  # @param [Number] intv Loop interval
  # @return [Number]
  def interval= intv
    validate_options(:interval => intv)

    @freq, @interval = [(intv == 0) ? nil : 1.0 / intv, intv]
    @interval
  end

  # @param [Hash] opts Options Hash.
  # @option opts [Numeric] :freq Frequency of loop execution (loops/sec)
  # @option opts [#call] :cond Loop condition
  # @private
  def initialize opts = {}
    validate_options opts

    freq, intv, @while = opts.values_at :freq, :interval, :while
    raise ArgumentError,
      "can't have both frequency and interval" if freq && intv

    @freq =
      if freq
        freq
      elsif intv
        (intv == 0) ? nil : 1.0 / intv
      else
        nil
      end
    @interval = @freq ? 1.0 / @freq : 0
  end
end

Instance Method Details

#loop(&block) ⇒ Object

Main loop

Parameters:

  • block (Proc) —

    Loop



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# File 'lib/lps.rb', line 24

def loop &block
  ret = nil
  always = @while.nil?

  if @freq.nil?
    while always || @while.call
      ret = block.call self

      # Frequency set!
      return loop(&block) if @freq
    end
  else
    nt = Time.now
    while always || @while.call
      ret = block.call self

      # Frequency unset!
      return loop(&block) unless @freq

      nt   += @interval
      now   = Time.now
      diff  = nt - now

      if diff > 0.01
        sleep diff
      elsif diff < 0
        nt = now
      end
    end
  end
  ret
end