From a recent query on The comp.lang.tcl newsgroup on combining 2 list into a single list:
Here is the test code used:
proc SET {l1 l2} { set l1 "$l1 $l2" }
proc APPEND {l1 l2} { append l1 " $l2" }
proc CONCAT {l1 l2} { set l1 [concat $l1 $l2] }
proc EVAL/LAPPEND {l1 l2} { eval [list lappend l1] $l2 }
proc FOREACH/LAPPEND {l1 l2} {foreach i $l2 {lappend l1 $i} ; set l1}
set cases "SET APPEND CONCAT EVAL/LAPPEND FOREACH/LAPPEND"
proc makeList {len item} {
for {set i 0} {$i< $len} {incr i} {
lappend res $item
}
return $res
}
proc testem {len} {
global cases
set res {}
foreach p $cases {
catch {unset l1}
catch {unset l2}
set l1 [makeList $len a]
set l2 [makeList $len b]
puts -nonewline stderr "$p..." ; flush stderr
lappend res $p,$len [lindex [time {llength [$p $l1 $l2]} 1000] 0]
}
return $res
}
foreach l {10 100 1000 10000} {
puts -nonewline stderr "testing size $l..." ; flush stderr
array set data [testem $l]
puts stderr done ; flush stderr
}
puts "Tcl Version - [info patchlevel]\n"
set fmtstr "| %15s | %6d | %6d | %6d | %6d |"
set divid "|-----------------|--------|--------|--------|--------|"
set ends "|-----------------------------------------------------|"
puts $ends
puts [format $fmtstr Method 10 100 1000 10000]
puts $divid
foreach p $cases {
puts [format $fmtstr $p \
$data($p,10) $data($p,100) \
$data($p,1000) $data($p,10000)]
}
puts $ends
And here are the results on an odler aplha box running Tru64 UNIX
<coming soon> Tcl 8.4a4 |-------------------------------------------| | Method | 10 | 100 | 1000 | 10000 | |-----------------|----|-----|------|-------| | SET | 21 | 148 | 6777 | 69467 | | APPEND | 29 | 475 | 7993 | 81514 | | CONCAT | 9 | 15 | 312 | 5968 | | EVAL/LAPPEND | 15 | 23 | 393 | 6065 | | FOREACH/LAPPEND | 18 | 369 | 4524 | 44235 | |-------------------------------------------|