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I have a text file that has thousands of questions and blanks for the answer, like this:

1) This is the first question 1)______

2) This is the second question 2)______

3)...

What I want to do is to extract the questions, and put them in a spreadsheet (I'm going to end up putting them in a database). I tried reading through Mathematica's Working with Strings page, but I couldn't figure out how to do it! Can someone please let me know how to do this? Thanks!

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I'll use a slightly modified example:

str = "1) This is the first question 1)______

 2) This is the second question 2)______

 ...

 10) This is the tenth question 10)______"

One can use either StringExpression[] or RegularExpression[] in StringCases[] for this; here's how:

StringTrim /@ StringCases[str,
                          n : DigitCharacter .. ~~ ")" ~~ s__ ~~ n_ ~~ ")" :> s]

or

StringTrim /@ StringCases[str, RegularExpression["(\\d+\\))(.+)\\1"] -> "$2"]

which should both yield {"This is the first question", "This is the second question", "This is the tenth question"}.

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    $\begingroup$ I wonder why people insist on hammering a screw and screwing a text processing problem $\endgroup$ Nov 11, 2015 at 6:13
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    $\begingroup$ Could've been worse; at least it wasn't parsing XML with regex. $\endgroup$ Nov 11, 2015 at 10:05
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    $\begingroup$ @NicolasJosephScozzaro Of course. I'm really glad you asked. For example, the unix-born text processing programs (now available on almost every platform) perl, awk or sed are much better suited for these tasks than Mathematica. Your problem is a one liner in any of them. In particular you're up and running in awk in -perhaps- one to three hours depending on your background, and it is a very nice language to learn $\endgroup$ Nov 11, 2015 at 15:37
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    $\begingroup$ @NicolasJosephScozzaro: There are great websites like regex101, where you can test regular expressions online. If you plan to do a lot of text processing, do yourself a favor and google for tutorials about regular expressions. They're not hard to use, and make text processing so much easier... $\endgroup$ Nov 11, 2015 at 17:52
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    $\begingroup$ @belisariushassettled, the Mathematica code at least in this answer is also a one-liner - can you give examples of one-liners in the Unix tools that take a lot more effort in M? $\endgroup$ Nov 11, 2015 at 18:06

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