RosettaCodeData/Task/Execute-a-Markov-algorithm/Tcl/execute-a-markov-algorithm-...

42 lines
1.2 KiB
Tcl

package require Tcl 8.5
if {$argc < 3} {error "usage: $argv0 ruleFile inputFile outputFile"}
lassign $argv ruleFile inputFile outputFile
# Read the file of rules
set rules {}
set f [open $ruleFile]
foreach line [split [read $f] \n[close $f]] {
if {[string match "#*" $line] || $line eq ""} continue
if {[regexp {^(.+)\s+->\s+(\.?)(.*)$} $line -> from final to]} {
lappend rules $from $to [string compare "." $final] [string length $from]
} else {
error "Syntax error: \"$line\""
}
}
# Apply the rules
set f [open $inputFile]
set out [open $outputFile w]
foreach line [split [read $f] \n[close $f]] {
set any 1
while {$any} {
set any 0
foreach {from to more fl} $rules {
# If we match the 'from' pattern...
if {[set idx [string first $from $line]] >= 0} {
# Change for the 'to' replacement
set line [string replace $line $idx [expr {$idx+$fl-1}] $to]
# Stop if we terminate, otherwise note that we've more work to do
set any $more
break; # Restart search for rules to apply
}
}
#DEBUG# puts $line
}
# Output the processed line
puts $out $line
}
close $out