Tcl Source Code

tailcall confuses the unknown handler of a namespace ensemble. The following script,

namespace eval ns1 {
    proc dispatch {routine args} {
        return list
    }
    namespace ensemble create -unknown [
    list ::apply [list {ensemble routine args} {
        tailcall dispatch $routine {*}$args
    } [namespace current]]]
}

puts [ns1 x one two three]

results in the error:

unknown subcommand "x": namespace ::ns1 does not export any commands

However, if the word "tailcall" is removed, then the result is as expected:

one two three