I looked at your link. This is more along the lines of if-then logic and I don't think that is what is being requested here.

My code above is more along the lines of if X OR Y happens, then we do Z. To be specific: (a)ignore any white space before or after the stuff that was typed in. (b) If "the stuff" (exclusive of leading or trailing white space) typed into the line is: q,Q,QUiT,quit or something similar in a upper or lower case insensitive manner then, the program stops - that's the "Z" action.

Update: the code is very specific about what it "needs":
Some more test cases shown below

C:\TEMP>stdcmdline.pl
Enter some text: quitme
quitme
Enter some text: quit me
quit me
Enter some text:    Quit me
   Quit me
Enter some text:   QuIt
program exited
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