File: //usr/lib/ruby/site_ruby/1.8/puppet/functions/scanf.rb
# Scans a string and returns an array of one or more converted values as directed by a given format string.args
# See the documenation of Ruby's String::scanf method for details about the supported formats (which
# are similar but not identical to the formats used in Puppet's `sprintf` function.
#
# This function takes two mandatory arguments: the first is the String to convert, and the second
# the format String. A parameterized block may optionally be given, which is called with the result
# that is produced by scanf if no block is present, the result of the block is then returned by
# the function.
#
# The result of the scan is an Array, with each sucessfully scanned and transformed value.args The scanning
# stops if a scan is unsuccesful and the scanned result up to that point is returned. If there was no
# succesful scan at all, the result is an empty Array. The optional code block is typically used to
# assert that the scan was succesful, and either produce the same input, or perform unwrapping of
# the result
#
# @example scanning an integer in string form (result is an array with
# integer, or empty if unsuccessful)
# "42".scanf("%i")
#
# @example scanning and processing resulting array to assert result and unwrap
#
# "42".scanf("%i") |$x| {
# unless $x[0] =~ Integer {
# fail "Expected a well formed integer value, got '$x[0]'"
# }
# $x[0]
# }
#
# @since 3.7.4
Puppet::Functions.create_function(:scanf) do
require 'scanf'
dispatch :scanf do
param 'String', 'data'
param 'String', 'format'
optional_block_param
end
def scanf(data, format)
result = data.scanf(format)
if block_given?
result = yield(result)
end
result
end
end