From OpenCog

The DontExecLink is a link type that prevents the execution of all atoms under it. It is similar to a QuoteLink; however, unlike a QuoteLink, it does allow variable substitution to be made into it. By contrast, quoted variables become constants, and cannot be grounded or beta-reduced.

It is typically used in a BindLink or a GetLink, to search and ground other BindLinks or GetLinks, without actually executing them.

An example/demo is needed.

This was added in pull req #714 to fix issue #704.

Perhaps this link should be retired, and replaced by LocalQuoteLink. See issue #992.