CODEWITHSUNDEEP
regex
Ilya Chernov
Ilya Chernov

Reputation: 431

Why do escape characters in regex mismatch?

  1. If I want to match the dot symbol (.) I have to write this regex:

    /\./

Escape character is needed to match the symbol itself.

  1. If I want to match the 'd' symbol I have to write this one:

    /d/

Escape character is not needed to match the symbol itself.

And if I want to match any character (/./) or any digit character (/\d/) it's vice versa.

It seems to me that this approach is not very consistent. What is the reasoning that stands behind it?

Thank you.

Upvotes: 3

Views: 135

Answers (1)

whatoncewaslost
whatoncewaslost

Reputation: 2256

The . character is a reserved regular expression keyword. The d isn't. You need to include the escape character when you match a period to explicitly tell regex that you want to use the period as a normal matching character. d by itself isn't a reserved word, so you don't need to escape it, but \d is a reserved word.

I can see how, to someone coming to regex it can be a little odd, but the . is used so often, and I can't think of a time I've really needed to match periods it just makes more sense to have it be one character without the backslash.

Upvotes: 5

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