On Thu, Jun 18, 2026 at 11:24 AM Phil Ratzloff <Phil.Ratzloff@sas.com> wrote:

They're used to guarantee that the functions needed by an algorithm are correctly defined. For instance, index_adjency_list requires vertices(g), out_edges(g,u) and others be defined, the underlying vertices(g) range is a random_access_range, the underlying out_edges(g,u) is a forward_range, etc.

Thank you so much, and I agree that graph concepts are useful. Yet evidence of utility is not the same as evidence of standardization need. What problem does standardization of graph concepts solve that can't be more cheaply solved by keeping it in the ecosystem (for example, keeping it on GitHub).

Thanks