module RSS::Utils

RSS::Utils is a module that holds various utility functions that are used across many parts of the rest of the RSS library. Like most modules named some variant of ‘util’, its methods are probably not particularly useful to those who aren’t developing the library itself.

Public Instance Methods

element_initialize_arguments?(args) click to toggle source

This method is used inside of several different objects to determine if special behavior is needed in the constructor.

Special behavior is needed if the array passed in as args has true or false as its value, and if the second element of args is a hash.

# File rss/utils.rb, line 124
def element_initialize_arguments?(args)
  [true, false].include?(args[0]) and args[1].is_a?(Hash)
end

get_file_and_line_from_caller(i=0) click to toggle source

Returns an array of two elements: the filename where the calling method is located, and the line number where it is defined.

Takes an optional argument i, which specifies how many callers up the stack to look.

Examples:

require 'rss/utils'

def foo
  p RSS::Utils.get_file_and_line_from_caller
  p RSS::Utils.get_file_and_line_from_caller(1)
end

def bar
  foo
end

def baz
  bar
end

baz
# => ["test.rb", 5]
# => ["test.rb", 9]

If i is not given, or is the default value of 0, it attempts to figure out the correct value. This is useful when in combination with instance_eval. For example:

require 'rss/utils'

def foo
  p RSS::Utils.get_file_and_line_from_caller(1)
end

def bar
  foo
end

instance_eval <<-RUBY, *RSS::Utils.get_file_and_line_from_caller
def baz
  bar
end
RUBY

baz

# => ["test.rb", 8]

# File rss/utils.rb, line 83
def get_file_and_line_from_caller(i=0)
  file, line, = caller[i].split(':')
  line = line.to_i
  line += 1 if i.zero?
  [file, line]
end

h(s)

Alias for: html_escape

html_escape(s) click to toggle source

Takes a string s with some HTML in it, and escapes ‘&’, ‘“’, ‘<’ and ‘>’, by replacing them with the appropriate entities.

This method is also aliased to h, for convenience.

Examples:

require 'rss/utils'

RSS::Utils.html_escape("Dungeons & Dragons")
# => "Dungeons &amp; Dragons"
RSS::Utils.h(">_>")
# => "&gt;_&gt;"

# File rss/utils.rb, line 103
def html_escape(s)
  s.to_s.gsub(/&/, "&amp;").gsub(/\"/, "&quot;").gsub(/>/, "&gt;").gsub(/</, "&lt;")
end

Also aliased as: h

new_with_value_if_need(klass, value) click to toggle source

If value is an instance of class klass, return it, else create a new instance of klass with value value.

# File rss/utils.rb, line 110
def new_with_value_if_need(klass, value)
  if value.is_a?(klass)
    value
  else
    klass.new(value)
  end
end

to_class_name(name) click to toggle source

Given a name in a name_with_underscores or a name-with-dashes format, returns the CamelCase version of name.

If the name is already CamelCased, nothing happens.

Examples:

require 'rss/utils'

RSS::Utils.to_class_name("sample_name")
# => "SampleName"
RSS::Utils.to_class_name("with-dashes")
# => "WithDashes"
RSS::Utils.to_class_name("CamelCase")
# => "CamelCase"

# File rss/utils.rb, line 27
def to_class_name(name)
  name.split(/[_\-]/).collect do |part|
    "#{part[0, 1].upcase}#{part[1..-1]}"
  end.join("")
end