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Highlights from
Automated composition of function handles

from Automated composition of function handles by Peter Cotton
Automatically compose function handles

isfun(f)
function y = isfun(f)
% function y = isfun(f)
%
% f   function_handle 
%
% Determine if f is annotated
try
    code = f('-fun');
    y = code==prod(double('fun'));
catch
    y = 0;
end

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