If matching for differences does not have to be done in Perl (tmtowtdi), and if you have the Vim editor, you can display the differences between up to four files. You may want to add the following "if" statement in your "_vimrc" file to make the differences stand out better. 

if &diff
    colorscheme clarity
    set diffopt=filler,context:0 "context displays 0 lines before and 
+after lines flagged as differrent.
endif

[download]

Start the Vim editor as follows:
(Note that on Windows, the "start" command frees up the command window while editing)
start /b gvim -d file1 file2

Once the diff screens are displayed, use the Vim normal mode command "zr" to display all hidden lines in both files.

Save the following text fragments to "file1" and "file2" for testing. 

file1:
A few moments will suffice to commit it to memory; yet the period whic
+h it
covers, commencing more than twenty-five centuries ago, reaches on fro
+m that
far-distant point past the rise and fall of kingdoms, past the setting
+ up and
overthrow of empires, past cycles and ages, past our own day, over int
+o the eternal state.

file2:
A few moments will suffice to commit it to memory, yet the period whic
+h it
covers, beginning more than twenty-five centuries ago, reaches from th
+at
far-distant point past the rise and fall of kingdoms, past the setting
+ up and
overthrow of empires, past cycles and ages, past our own day, to the e
+ternal state.

[download]

"It's not how hard you work, it's how much you get done."

In reply to Re: Comparing two text files and marking differences by roho
in thread Comparing two text files and marking differences by Polyglot

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