**Introduction**
This page is made to collect as many as possible of TCL procedures that play with the positions of the words of a string or the characters' position in a string while they don't exist in the manual. Add and share as many as you can.
Please try to follow the formatting of this page for easy access.

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**Reversing The Order Of The Words**

Author: Rani Fayez Ahmad [Superlinux]

***The Given***

We have a string like this: 

======
 Rani is here too
======

We want to have it as :

======
 too here is Rani
======

Also regardless of the number of spaces between the words, we should do word order reversal.

***The Solution***


======

proc reverse_word_order { all_original_text } {
# 1- Reverse the orignial text
set reversed [ string reverse  $all_original_text] 

# 2- split the reversed string $reversed into a list of words then loop over them
set list_of_reversed_words [split $reversed  ]

foreach reversed_words $list_of_reversed_words {

# 3- find the indices of the extremes of each reversed word in the $reversed

set word_start [ string first $reversed_words $reversed $word_start]
set word_end [ expr $word_start -1 + [string length $letter] ]

# 4- reverse the current-in-the-loop reversed word back to its normal state, e.g: 
# if i have a word "loohcs" then convert it by reversing it to "school"

set original_word [string reverse [ string range $reversed $word_start $word_end] ]

# 5- replace  the reversed word (loohcs) with the correcte one (school)

set reversed [ string replace $reversed $word_start $word_end $original_word]

# 6- set the start-of-search index to the index 
# directly after the ending of the current word

set word_start [expr $word_end +1]

# 7-continue to the next loop  
}

#print the result
return $reversed
}
======


***Another Simpler Solution***

This uses regular expressions.


======
proc reverse_word_order {str} {

#1-Reverse the whole string

set $reversed_str [string reverse $str]

#2- split the reversed string into a list of words
set reversed_words [ split $reversed_str]

#3- reverse and replace  every word occurrence in the reversed string
foreach word $reversed_words {

      regsub -all "\\m$word\\M" $reversed_str [string reverse $word] reversed_str   


}

return $reversed_str
}
======

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***Modern Solution***

Perhaps this might do?

======
   proc w-reverse { string } {    lreverse $string }
======

[Ro] Realistically this will break when your string doesn't evaluate as a valid tcl list. 

[jbr] OK -- then how's this:

======
   proc w-reverse { string } { join [lreverse [regexp -inline -all -- {\S+} $string]] }
======

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**Get the list of all ASCII (Latin/Greek/Russian) sentences/strings**

Author: Rani Fayez Ahmad [Superlinux]

***The Given***
Lets say we have a mixture of ASCII words and Unicode words in a string, for example Arabic and Latin words, and we want to extract
continuous sequences of ASCII characters and put them into a TCL [[[list]]]. Also, in the result, add to the list the starting index of each ASCII part. Lets say we have this as an example input :

======
set y "hello all peoebla كنتمنبستيى  اتياتاتايب ما غغخعاتلا  jhjhfdyigrwyih hruiehbbqbcvvb jenhwcbebeمااخؤصىقلاقىاؤ تااقصىقرثالا  khwbvbrehb"
======

What I should get is this :

======
{{hello all peoebla } 0} {{  jhjhfdyigrwyih hruiehbbqbcvvb jenhwcbebe} 52} {{  khwbvbrehb} 121}
======

***The Solution***

======

proc list_of_all_ascii_parts_a_unicode_string { arabic_string} {

set ascii_parts_list [list]
set length [string length $arabic_string]
   for {set i 0} { $i< $length } {incr i } {
      set start_of_ascii $i
      
      
     
      set end_of_ascii  $start_of_ascii 
      while { [string is ascii [string range $arabic_string $start_of_ascii $end_of_ascii]] ==  1  && $i<$length }  {
      
      puts [string range $arabic_string $start_of_ascii $end_of_ascii]
      incr i
      incr end_of_ascii 
      }
      
      incr end_of_ascii -1
      
      set ascii_part  [ string range $arabic_string $start_of_ascii $end_of_ascii]
      
      if { [string trim $ascii_part] !="" } {
        
        set ascii_parts_list [ linsert $ascii_parts_list end [list $ascii_part $start_of_ascii ] ]
      
      }
    }
    
    return $ascii_parts_list
}
======

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[AMG]: For history on this page dated 2013 and older, see [http://wiki.tcl.tk/_/history?N=38277].

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