Question about input of scanners in flex

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SUMMARY

The discussion centers on the definitions of CHARCON and BAD_CHARCON in the context of regular expressions used in programming. CHARCON is defined as a set of characters that can be included in a string, while BAD_CHARCON includes characters that are considered invalid or problematic. The use of escape sequences and special characters in these definitions is crucial for understanding how input is processed by scanners in programming languages. The conversation emphasizes the importance of context when interpreting these regular expressions.

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Homework Statement


I have the following set of definitions

CHARCON ('([^\\'\n]|\\[\\'"0nt])')
BAD_CHARCON ('([^\\'\n]|\\[\\'"0nt]|\\[^\\'"0nt])?[']?[\n]?)

My questions are what is a charcon?, why does it have such weird characters and why are the characters of BAD_STRINGCON bad characters?

Homework Equations

The Attempt at a Solution

 
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You need to consider these in the context of the program where they are found if you hope to make sense out of them. These expressions are composed of what are known as regular expressions.

In the absence of context, I can imagine that CHARCON might be those CHARACTERS which are allowed to be CONTAINED within whatever it is that the routine will process. Google might be able to help you here.

Perhaps this thread would be a better fit in our Programming & Computer Science forum?
 

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