Add join_keys_to_values function

This commit adds a function that joins each of a hash's keys with that
key's corresponding value, separated by a separator string. The
arguments are a hash and separator string. The return value is an
array of joined key/value pairs.

1 files changed, 47 insertions, 0 deletions

diff --git a/lib/puppet/parser/functions/join_keys_to_values.rb b/lib/puppet/parser/functions/join_keys_to_values.rb
new file mode 100644
index 0000000..e9924fe
--- /dev/null
+++ b/lib/puppet/parser/functions/join_keys_to_values.rb
@@ -0,0 +1,47 @@
+#
+# join.rb
+#
+
+module Puppet::Parser::Functions
+  newfunction(:join_keys_to_values, :type => :rvalue, :doc => <<-EOS
+This function joins each key of a hash to that key's corresponding value with a
+separator. Keys and values are cast to strings. The return value is an array in
+which each element is one joined key/value pair.
+
+*Examples:*
+
+    join_keys_to_values({'a'=>1,'b'=>2}, " is ")
+
+Would result in: ["a is 1","b is 2"]
+    EOS
+  ) do |arguments|
+
+    # Validate the number of arguments.
+    if arguments.size != 2
+      raise(Puppet::ParseError, "join_keys_to_values(): Takes exactly two " +
+            "arguments, but #{arguments.size} given.")
+    end
+
+    # Validate the first argument.
+    hash = arguments[0]
+    if not hash.is_a?(Hash)
+      raise(TypeError, "join_keys_to_values(): The first argument must be a " +
+            "hash, but a #{hash.class} was given.")
+    end
+
+    # Validate the second argument.
+    separator = arguments[1]
+    if not separator.is_a?(String)
+      raise(TypeError, "join_keys_to_values(): The second argument must be a " +
+            "string, but a #{separator.class} was given.")
+    end
+
+    # Join the keys to their values.
+    hash.map do |k,v|
+      String(k) + separator + String(v)
+    end
+
+  end
+end
+
+# vim: set ts=2 sw=2 et :