Question

I am trying to search string pattern using regular expression

But since I am very new to regular expression I would like to ask some advice on search pattern

So, I would like to find a line which has ‘value’ as below
value can be both numbers and alphabets

Name (value)

I tried to use pattern

re.search(r"Name \([a-zA-Z0-9]\)", line)

But it doesn’t seem to find as I expected.

How should I write search pattern?
Thank you!

Answer 1

Your expression is fine but your character group lacks a quantifier:

re.search(r"Name \([a-zA-Z0-9]+\)", line)

The + means “at least one of those”. If you don’t put a quantifier it means only one of the mentioned characters may occur. Possible quantifiers are:

• + for one or more,
• ? for at most one and
• * for any number of those
• {x,y} works as well, meaning at least x, but at most y characters

And the quantifier always refers to what you place right before it, which might be a single character or a character group enclosed in [].

Edit: As mentioned in the comments by root you might want to look at \w, which is a short notation for “all word characters”. It includes all letters and digits, as well as the underscore and maybe special characters if they are specially defined by the current locale.