foreach vs. foreach vs. foreach

proc a {list1} {
    foreach item $list1 {
	lappend a $item
    }
}

proc b {list1} {
    time {
	foreach item $list1 {
	    lappend a $item
	}
    } 10
}

for {set i 0} {$i < 100000} {incr i} {
    lappend list1 $i
}
puts [time {a $list1} 10]
puts [b $list1]
puts [time {
    foreach item $list1 {
	lappend a $item
    }
} 10]