Tcl: how to print one set - tcl

Question

My file to be parsed is like this
Name : John
Pin : 5400
Age : 40
Place: Korea
Amount : 4000
Name : Peter
Pin : 6700
Age : 10
Place : Japan
Amount : 3600
My tcl code is
set start "Name"
set pn "Pin"
set ag "Age"
set ag_cutoff 15
set amnt "Amount"
foreach line [split $content "\n"] {
if {[regexp $start $line]} {
set count 1
set l1 $line
}
if {[regexp $pn $line] && $count ==1} {
set pin_val [lindex $line 2]
set l2 $line
}
if {[regexp $ag $line] && $count ==1} {
set ag [lindex $line 2]
if { $ag > $ag_cutoff} {
set rep_taken 1
set l3 $line
}
if {[regexp $amnt $line] && $count ==1 && $rep_taken == 1} {
set age_val [lindex $line 2]
puts $op1 "$ag $age_val "
puts $op2 "$l1\n$l2\n$l3\n"
}
This code is fine for plots.
However, I also want to o/p a file with complete set where $ag>$ag_cutoff.
Now with puts $op3 "$l1\n$l2\n$l3\n" ---> Able to print to a file. But how to print line Place which is not evaluated. Any better way to accomplish this.
Name : John
Pin : 5400
Age : 40
Place : Korea
Amount : 4000

Answer 1

It would be a lot simpler to let the parsing loop just create a dictionary (this replaces your code above):
set data {}
set count 0
foreach line [split $content \n] {
if {[lindex $line 0] eq "Name"} {
incr count
}
dict set data $count [lindex $line 0] [lindex $line 2]
}
This will blow up if the first line doesn't start with "Name", or if there is a missing blank between a colon and a word, and also if a value consists of several words. All of these are easy to fix.
Here, for instance, is an expanded version that takes care of the last two problems, should they occur:
set data {}
set count 0
foreach line [split $content \n] {
set keyword [string trimright [lindex $line 0] :]
set value [string trimleft [lrange $line 1 end] {: }]
if {$keyword eq "Name"} {
incr count
}
dict set data $count $keyword $value
}
When all records are stored, one can output selected records using dictionary iteration:
set ag_cutoff 15
dict for {count record} $data {
if {[dict get $record Age] > $ag_cutoff} {
dict for {k v} $record {
puts "$k : $v"
}
}
}
This also means that you can keep adding fields to the records, and the code will still work without change.
Precautions
If the data in content has empty lines at the beginning or end, or between some lines, these methods won't work. A simple way to guard against empty or blank lines at the beginning or the end is to replace
foreach line [split $content \n] {
with
foreach line [split [string trim $content] \n] {
If empty / blank lines may occur within the data, one can use this to skip them:
foreach line [split $content \n] {
if {[string is space $line]} continue
If one is 100% sure that all data is in proper list form, it is possible (but a bit code-smelly) to use list commands like lindex on it directly. If one is less sure, or if one wants to be more correct, one should convert each line to a list before working on it:
foreach line [split $content \n] {
set line [split $line]
Documentation: dict, foreach, if, incr, lindex, lrange, puts, set, split, string