Victor,
Is it possible to have an alias to ensemble or multi-word commands?
Well, namespace ensembles are straight forward; you may find out the ensembled Tcl commands using e.g. [namespace ensemble configure string -map] and then use the fully-qualified command names as alias target:
package req nx::test
Object create o { :public alias stringLength ::tcl::string::length }
? {o stringLength "xyz"} [string length "xyz"]
If you don't have an ensemble command at hand (e.g., the [string is] classes such as "integer", "boolean"), you want to bind in terms of a method, consider a forwarder:
o public forward stringIsBoolean string is boolean
? {o stringIsBoolean "false"} [string is boolean "false"]
A forwarder is needed, because the "boolean" selector does not map to a Tcl command, rather is an argument to a paramteric Tcl command (::tcl::string::is).
A mixed alternative would be ...
o public alias stringIs ::tcl::string::is o public forward stringIsBoolean2 %self stringIs boolean
? {o stringIsBoolean2 "false"} [string is boolean "false"]
//stefan