wdb This command shows or extends the namespace where an input command is searched in.
In this example, the namespace is extended:
% namespace path "tcl::mathfunc tcl::mathop" %
Now, you can input math-related commands as follows:
% hypot 3 [+ 2 2] 5.0 %
In this example, the namespace extension is shown.
% namespace path ::tcl::mathfunc ::tcl::mathop %
Note that the namespaces argument is one proper list. It is not possible to input namespaces as single arguments. (Is it a matter of discussion if that should be possible?)
Note that each namespace (including the global namespace) has a different path. For example:
% namespace eval test {namespace path ::tcl::mathop}
%inside newly created namespace test, path is extended to ::tcl::mathop. Now, check it out:
% namespace eval test {namespace path}
::tcl::mathop
%Indeed, path is extended. Now check it in namespace ::
% namespace path %
In namespace ::, obviously there is no path extension. Check if ::tcl::mathop::+ is known in namespace test:
% namespace eval test {+ 5 6}
11
%Check the samein namespace :: leads to failure:
% + 5 6 invalid command name "+" %