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C. An Incredibly Brief Guide to Regular ... > What Regular Expressions Do
What Regular Expressions Do
Regular expressions help your programs find chunks of text that match patterns you specify. Depending on how you call the regular expression, you may get:
- A yes/no answer
-
Something matched or it didn’t
- A set of matches
-
All of the pieces that matched your query, so you can sort through them
- A new string
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If you specified that this was a search-and-replace operation, you may have a new string with all of the replacements made
Regular expressions also offer incredible flexibility in specifying search terms. A key part of the reason that regular expressions look so arcane is that they use symbols to specify different kinds of matches, and matches on characters that aren’t easily typed.