isfun: a pedestrian matlab construct determiner

determines the definition of ML constructs

res = isfun(arg1,arg2,'-opt',...,argN,'-opt')

determines the definition of ML constructs arg1 ... argN and
returns result-code(s)
in <res>
res.f(x) = arg(x)
res.r(x) = code(x)

SEE
help isfun
for more exhaustive explanations of precedence, return-codes and options

isfun -h
for examples

EXAMPLES
r=rand(1,2,3,4);
e=isfun(r,'r',1:5,'inline',@inline,'sin','sin.m',@sin);
% + double <r> (1,2,3,4) / 192 bytes
% + variable <r> [ var <r>]
% - double <r> (1,2,3,4) / 192 bytes [-: type of <r>]
% + double <*> (1,10) / 80 bytes [*: unnamed]
% + function [ 1/ -1] <MLROOT\toolbox\matlab\funfun\@inline\inline.m>
% + function handle <@inline>
% - function [ 1/ -1] <MLROOT\toolbox\matlab\funfun\@inline\inline.m>
% + built-in function <sin>
% + script <MLROOT\toolbox\matlab\elfun\sin.m>
% + function handle <@sin>
% - built-in function <sin>