avoid needing to include hdf5 in public header files (bug #44370, #43180) * oct-hdf5-id.cc, oct-hdf5-id.h: New files. * libinterp/corefcn/module.mk: Update. * libgui/src/module.mk (src_libgui_src_la_CPPFLAGS): Remove $(HDF5_CPPFLAGS) from the list. * load-save.h (enum load_save_format_type): Always include LS_HDF5 in the list of values. * ls-hdf5.cc (read_hdf5_data, save_hdf5_data): Call check_hdf5_id_type. * oct-hdf5.h: Also #define HDF5_SAVE_TYPE. * ov.h, ov-base.h: Include oct-hdf5-id.h instead of oct-hdf5.h. Always declare load_hdf5 and save_hdf5 functions. * ov-base-int.cc, ov-base-int.h, ov-base.cc, ov-bool-mat.cc, ov-bool-mat.h, ov-bool-sparse.cc, ov-bool-sparse.h, ov-bool.cc, ov-bool.h, ov-cell.cc, ov-cell.h, ov-class.cc, ov-class.h, ov-complex.cc, ov-complex.h, ov-cx-mat.cc, ov-cx-mat.h, ov-cx-sparse.cc, ov-cx-sparse.h, ov-fcn-handle.cc, ov-fcn-handle.h, ov-fcn-inline.cc, ov-fcn-inline.h, ov-float.cc, ov-float.h, ov-flt-complex.cc, ov-flt-complex.h, ov-flt-cx-mat.cc, ov-flt-cx-mat.h, ov-flt-re-mat.cc, ov-flt-re-mat.h, ov-int16.cc, ov-int32.cc, ov-int64.cc, ov-int8.cc, ov-lazy-idx.h, ov-oncleanup.cc, ov-oncleanup.h, ov-range.cc ov-range.h, ov-re-mat.cc, ov-re-mat.h, ov-re-sparse.cc, ov-re-sparse.h, ov-scalar.cc, ov-scalar.h, ov-str-mat.cc, ov-str-mat.h, ov-struct.cc, ov-struct.h, ov-uint16.cc, ov-uint32.cc, ov-uint64.cc, ov-uint8.cc: Move #ifdef HAVE_HDF5 inside load_hdf5 and save_hdf5 functions. Always declare and define load_hdf5 and save_hdf5 functions.

%!test
%! % Work around MATLAB bug where f(x)(y) is invalid syntax
%! % (This bug does not apply to Octave)
%!
%! C = @(fcn,x) fcn(x);
%! C2 = @(fcn,x,y) fcn(x,y);
%!
%! % Church Booleans
%! T = @(t,f) t;
%! F = @(t,f) f;
%!
%! % Church Numerals
%! Zero  = @(fcn,x) x;
%! One   = @(fcn,x) fcn(x);
%! Two   = @(fcn,x) fcn(fcn(x));
%! Three = @(fcn,x) fcn(fcn(fcn(x)));
%! Four  = @(fcn,x) fcn(fcn(fcn(fcn(x))));
%!
%! % Arithmetic Operations
%! Inc = @(a) @(f,x) f(a(f,x)); % Increment
%! Add = @(a,b) @(f,x) a(f,b(f,x));
%! Mult = @(a,b) @(f,x) a(@(x) b(f,x),x);
%! Dec = @(a) @(f,x) C(a(@(g) @(h) h(g(f)), @(u) x), @(u) u); % Decrement
%! Sub = @(a,b) b(Dec, a);
%!
%! % Renderer - Convert church numeral to "real" number
%! Render = @(n) n(@(n) n+1,0);
%!
%! % Predicates
%! Iszero = @(n) n(@(x) F, T);
%!
%! % Y combinator implements recursion
%! Ycomb = @(f) C(@(g) f(@(x) C(g(g), x)), ...
%!                @(g) f(@(x) C(g(g), x)));
%!
%! Factorial = Ycomb(@(f) @(n) C(C2(Iszero(n), ...
%!                   @(d) One, @(d) Mult(n, f(Dec(n)))),0));
%!
%! assert (Render (Factorial (Two)), 2)
%! assert (Render (Factorial (Three)), 6)
%! assert (Render (Factorial (Four)), 24)