Parses the delay and url from the content attribute of a meta tag. Parse requires the uri of the current page to infer a url when no url is specified. If a block is given, the parsed delay and url will be passed to it for further processing.

Returns nil if the delay and url cannot be parsed.

  # <meta http-equiv="refresh" content="5;url=http://example.com/" />
  uri = URI.parse('http://current.com/')

  Meta.parse("5;url=http://example.com/", uri)  # => ['5', 'http://example.com/']
  Meta.parse("5;url=", uri)                     # => ['5', 'http://current.com/']
  Meta.parse("5", uri)                          # => ['5', 'http://current.com/']
  Meta.parse("invalid content", uri)            # => nil

[Source]

    # File lib/mechanize/page/meta.rb, line 31
31:         def parse(content, uri)
32:           if content && content =~ CONTENT_REGEXP
33:             delay, url = $1, $3
34: 
35:             url = case url
36:                   when nil, "" then uri.to_s
37:                   when /^http/i then url
38:                   else "http://#{uri.host}#{url}"
39:                   end
40: 
41:             block_given? ? yield(delay, url) : [delay, url]
42:           else
43:             nil
44:           end
45:         end