Why another parsing-routine? Because the other ones like cmdline or OptProc are a little overweighted or just too complex. Here in the wiki, I found links to various usefull parsing-routines, but still I decieded to write one of my own; here is the result. The input is checked/processed against a template, and the result is given back as a list suitable for array set. Switchnames may be shortened. At the bottom of the page later I will add some examples of how a commandline and the corresponding templates can look like.
# Simple ParameterParsing (SPar)
# 08.03.2005
proc spar {tpl cmd} {
if {[catch {array set a $tpl}]} {
return -code error {invalid template}; # we could'nt handle this error
}; # don't stop with other errors - give pgmr the chance to decide later
set needmore {}
set count 0
set seeopts 1
foreach item $cmd {
if {[string equal $item "--"]} {
set seeopts 0; # end of -flag-processing
} elseif {[string length $needmore]} {
set a($needmore) $item
set needmore {}
} elseif {$seeopts == 1 && [string range $item 0 0] == "-"} {
set matches [array names a -glob $item*]; # allows shortening
if {[llength $matches]} {
set match [lindex [lsort $matches] 0]
if {[string index $match end] == ":"} {
set needmore $match; # -f: means: 'value follows'
} else {
set a($match) 1; # otherwise simply return 'true'
}
} else {
lappend a(swiunknown) $item
}
} else {
incr count; # each arg counts, even if there are too much
if {[info exists a($count)]} {
set a($count) $item
set a(argcount) $count
} else {
lappend a(argsuper) $item
}
}
}
if {[string length $needmore]} {
set a(swinovalue) $needmore; # missing value after -switch: at the very end
}
return [array get a]; # double conversion is the price for using arrays
} # Tests
set tpl [list -f1 0 -f2 0 -f3: "*" -f4 0 -test 0 1 "" 2 "" 3 "Default3" -? 0]
puts "Template: $tpl\n"
puts Commandline:
gets stdin cmd
if {![catch {array set a [spar $tpl $cmd]} rc]} {
puts "Resultarray:\n"
parray a
} else {
puts $rc
}(Examples will be added later)