Appreciate the response but do not think this answers my question. Maybe I did not explain myself properly. I would like the foo object to return a (boost) range object that the caller can traverse without knowing the details of the internal structure. The foo object might contain a configurable number of vector of int. So in one scenario foo will be initalized like this; vec = { {1,2,3}, {4,5,6}, {7,8,9} }; and in another scenario like this; vec = { {1,2,3}, {4,5,6}, {7,8,9}, {10,11,12} }; I do not want to create another vector "master" that contains all int. Appreciate any input 🙂 kind regards, Lars ________________________________ Fra: degski <degski@gmail.com> Sendt: søndag 5. april 2020 23:08 Til: Boost users list <boost-users@lists.boost.org> Kopi: Lars Sunde <laasunde@hotmail.com> Emne: Re: [Boost-users] boost range dynamic joined_range On Sun, 5 Apr 2020 at 14:31, Lars Sunde via Boost-users <boost-users@lists.boost.org<mailto:boost-users@lists.boost.org>> wrote: The following code compile on Visual Studio 2017 and will output the number 1 to 9. This code will do so: https://stackoverflow.com/a/50660987 . degski -- @systemdeg "We value your privacy, click here!" Sod off! - degski "Anyone who believes that exponential growth can go on forever in a finite world is either a madman or an economist" - Kenneth E. Boulding "Growth for the sake of growth is the ideology of the cancer cell" - Edward P. Abbey