= pan/functions Template =
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Several pan programming patterns or idioms occur frequently in machine configurations.  The functions defined in the "pan/functions" template provide shortcuts to using those idioms.  To access the functions, the template must be included in the machine configuration:
{{{
  include { 'pan/functions' };
}}}
After this is included, any of the defined functions can be used from within DML blocks.

== 'self' Utility Functions ==

Often one want to add elements to a resource (list or hash) incrementally with a sequence of assignment statements.  Those assignment statements usually being in different templates.  The following functions provide simple mechanisms to do so.

"""push(element...) """
This function will return a copy of self with the given value(s) appended to the end.  If self is undefined, the function will create a new list with the arguments and return that.  An example is 
{{{
  '/mylist' = push('a');
  '/mylist' = push('b');
}}}
The final value for '/mylist' will be a two-element list containing 'a' and 'b'.  

Be careful, however, because the value of self is not directly modified by the push() function.  This means that the following:
{{{
  '/mylist' = {
    push('a');
    push('b');
  };
}}}
will leave '/mylist' with the one-element list 'b'.

   

== 'object' Utility Functions ==