How do I make a regular expression for all special characeters in OCaml?

Learning
1

How do I make a regular expression for all special characeters in OCaml?

there should be 32 of them.

2

Your other questions have been about ocamllex and not so much about OCaml itself. So I’ll assume you want to know how to make a pattern in ocamllex that matches any single character with a character code between 0 and 31.

A rule like this should do what you want:

let special = ['\x00' - '\x1f']

Note that this is exactly the same as your rule for digit except that the range of characters is different.

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3

I want to exclude " and \, how do I do that?

4

Yes I did mean Ocamlex, I forget they are different since they are so related.

6

The two characters '"' and '/' are not matched by the special rule as it stands. So it doesn’t make sense to exclude them.

However, to exclude characters from a set you can write a # b , which denotes the characters in set a but not in b.

(Rather than asking a series of brief questions here, I would recommend reading through the documentation. It will be faster in the long run.)

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