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Calling functions

Important note: all examples follow aTbRef naming conventions.

Calling functions from action code

Regardless of where stored, every function in the current document can be called from any action.

If a function has arguments, the caller must supply values for each argument, even if only as an empty string (or other default data-type value. Extra arguments are ignored. If a function is redefined, the most recent definition replaces any existing definitions.

If the called function returns a value, then the calling code needs to use an attribute or variable to receive that value.

Examples—with a return value

Calling a single literal value for an argument:

$MyNumber = fAddTax(500); 

Calling a function with a single argument:

$Text = fMakeTable($CategoryList); 

Calling a function with multiple arguments, that returns List-type data (see here for multi-value returns):

$MyList = fAlterList($CategoryList,$SomeString,"alternate"); 

A function with no arguments:

$MyNumber = fCheckSum(); 

Notice how in every case the function is called as the right side of an '=' (i.e. value assignment) operation so the return value can be stored and further used.

Example—with no return value

A function with no return value:


Note in this case that whilst no left-side recipient is needed but function parentheses must be included.

Can a function call another function?

Yes. A function can call itself. This is called 'self-reference', and is an advanced technique that should be used with caution and tested in a test document before use at scale. This process is also known as recursion.

Next: Variable use in functions