version conflict for package "struct::graph": have 1.2.1, need 2.0
    while executing
"package require struct::graph     2.0"
    (in namespace eval "::request" script line 2)
    invoked from within
"namespace eval ::request $script"
    ("::try" body line 12)
OUTPUT BUFFER:
package require Tcl 8.2
package require struct::graph     2.0
package require struct::queue     1.2.1
package require struct::stack     1.2.1
package require struct::tree      2.0
package require struct::matrix    2.0
package require struct::pool      1.2.1
package require struct::record    1.2.1
package require struct::list      1.4
package require struct::set       2.1
package require struct::prioqueue 1.3
package require struct::skiplist  1.3

namespace eval ::struct {
    namespace export *
}

package provide struct 2.1