18.3: Recursive Functions
- Page ID
- 54380
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A recursive function declaration must be preceded by the keyword recursive. In addition, the keyword result must be explicitly added to the function declaration. The result keyword is used to specify a single variable for the return value. Similar to a standard function, the result variable must be set to a return value to the calling routine.
The function type specifies the type of the result variable. For example:
<type> recursive function <name> (<arg's>) result (<variable>)
<declarations>
<body of function>
<variable> = expression
return
end function <name>
The main does not need any special declarations.