coyotes rand mair fheal wrote in the comp.lang.tcl newsgroup:
proc rangedswitch {index switches} {
for {set i 0} {$i<[llength $switches]} {incr i} {
if {[string equal $switches([expr {$i+1}]) ..]} {
set match [expr {$switches($i)<=$index &&$index<=$switches([expr {$i+2}])}]
incr i 2
} else {
set match [expr {$switches($i)==$index}]
}
et cetera
rangedswitch $i {
0 {do a}
2 .. 5 {do b}
}* Could someone elaborate on this? It won't work as-is. -- Sy / jrandomhacker.info
RS rather reinvented that wheel, slightly different of course - see the test at end:
proc rswitch {value body} {
set go 0
foreach {cond script} $body {
if {[regexp {(.+)\.\.(.+)} $cond -> from to]} {
if {$value >= $from && $value <= $to} {incr go}
} else {
if {$value == $cond} {incr go}
}
if {$go && $script ne "-"} { #(2)
uplevel 1 $script
break
}
}
if {$cond eq "default" && !$go} {uplevel 1 $script} ;#(1)
}Testing:
% foreach i {0 1 2 3 4 5 6 7 8} {puts $i;rswitch $i {1 {puts yes} 2..5 {puts maybe} 6..8 {puts no}}}
0
1
yes
2
maybe
3
maybe
4
maybe
5
maybe
6
no
7
no
8
noDue to polymorphic comparison (numeric or string), this also works:^)
% foreach i {A K c z 0 7} {
puts $i;rswitch $i {A..Z {puts upper} a..z {puts lower} 0..9 {puts digit}}
}
A
upper
K
upper
c
lower
z
lower
0
digit
7
digit* Ok, that's useful stuff.. but what about multi-digit numbers? -- Sy / jrandomhacker.info
e.g., using:
rswitch 100 {A..Z {echo upper} a..z {echo lower} 0..999 {echo digit}}RS Yup, my bug. ".." in regular expressions match any char, so the original version
if {[regexp (.+)..(.+) $cond -> from to]} {was over-eager - in 0..99, it matched "0." as from, and "9" as to. Fixed above, so multi-digit numbers work (and added a line for default treatment at #(1)). Another enhancement at #(2) is fall-through treatment (a - b - c ...} just like in switch. Thanks for testing!
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