* nsf.c (NextSearchAndInvoke): Relax the pre-conditions, objv can actually be NULL (see test cases). Besides, the assertion was not reflected by a corresponding nonnull constraints on the NextSearchAndInvoke prototype.
execution namespace reform: - add execution namespace to proc context instead of altering the namespace of the command - this fixes strange behavior of "info commands ::o::p", which might have returned "::p" - provide compatibility with Tcl 8.7a2 - extend regression test