proc closure {env params body} {
    set ns [uplevel 1 { namespace current }]
    set body [list with __scope__ $body]
    set lambda [list $params $body $ns]
    return [list $env $lambda]
}
proc with {scopeVar body} {
    uplevel 1 [list upvar 1 $scopeVar __scope__]
    uplevel 1 [list dict with __scope__ $body]
}
proc applyc {closureVar args} {
    upvar 1 $closureVar closure
    lassign $closure __scope__ lambda
    try { apply $lambda {*}$args } on ok result { set closure [list $__scope__ $lambda]; return $result }
}
proc invokec {args} {
    uplevel 1 {*}$args
}
 
set i -1
 
set counter [closure {i 0} {{n 1}} { incr i $n }]
 
puts "MAIN: [applyc counter]"
puts "MAIN: [applyc counter]"
 
proc test {localcounter} {
    puts "TEST: [applyc localcounter]"
    puts "TEST: [applyc localcounter]"
}
 
test $counter
 
puts "MAIN: [applyc counter]"
puts "I: $i"

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