octave: Private Functions
11.9.3 Private Functions
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In many cases one function needs to access one or more helper functions.
If the helper function is limited to the scope of a single function,
then subfunctions as discussed above might be used. However, if a
single helper function is used by more than one function, then this is
no longer possible. In this case the helper functions might be placed
in a subdirectory, called "private", of the directory in which the
functions needing access to this helper function are found.
As a simple example, consider a function ‘func1’, that calls a helper
function ‘func2’ to do much of the work. For example:
function y = func1 (x)
y = func2 (x);
endfunction
Then if the path to ‘func1’ is ‘<directory>/func1.m’, and if ‘func2’ is
found in the directory ‘<directory>/private/func2.m’, then ‘func2’ is
only available for use of the functions, like ‘func1’, that are found in
‘<directory>’.