[SOLVED] What does .* mean?

[eXeCuTeR]

What does the .* mean?

I know it's 2 tags and not 1 but sometimes people write it and it seems so stupid for me.

Why?

. means all characters except \n

* means 1 or more characters.

 

and sometime they end it like this:

.*?

Would you please explain me this?

Thanks.

[effigy]

. is a metacharacter which matches all characters except a new line. It encompasses all characters if the /s modifier is used.

 

* is a quantifier which will try to match as many characters as possible, but is allowed to match nothing at all.

 

Adding a ? to a quantifier makes it lazy. By default, all quantifiers try to match their maximum first. When made lazy, they try to match their minimum first.

[eXeCuTeR]

You didn't answer my question.

 

Why do they use . and then * together?

 

Thanks for the explanation tho.

[effigy]

Quantifiers quantify things. If you only use . it means match one instance. When you add * you modify the quantity of ., which then looks for 0 to any number of instances of ., instead of only one.

 

See this page for more information.

[eXeCuTeR]

Oh, the . quantifier matches only 1 character?

[Azu]

. matches one character

.* matches 0 to infinity characters

.+ matches 1 to infinity characters

 

. is like .{1,1}

.* is like .{0,9999999999999999999999}

.+ is like .{1,9999999999999999999999}

[effigy]

Oh, the . quantifier matches only 1 character?

 

. is not a quantifier--it's a metacharacter.

 

Anything without a quantifier is expected to match once. It makes sense if you think about it. If you type "a" in your pattern, you expect it to match just "a"--not "aa", "aaa", "aaaaa", etc. Therefore, this same logic applies to metacharacters.

[eXeCuTeR]

Thanks guys, you helped me

[Daniel0]

.* is like .{0,9999999999999999999999}

.+ is like .{1,9999999999999999999999}

 

Err... no it isn't. * corresponds to {0,} and + corresponds to {1,}

[Azu]

No need to be a smartass. We know it doesn't literally mean that number I posted. I was just trying to explain in a way that would be easily understandable since he doesn't know much about regex.

[effigy]

No need to be a smartass. We know it doesn't literally mean that number I posted. I was just trying to explain in a way that would be easily understandable since he doesn't know much about regex.

 

What Daniel posted is the correct syntax for those quantifiers. Just because "we" know, doesn't mean the people reading this post do. There's no need to call someone a smart ass for correcting you.

[Azu]

Okay I think there's a misunderstanding.

 

I was trying to explain how the quantifiers work to the person that did not understand how they work. So saying {1,} probably would have made no sense to him. It's usually safe to assume that a long line of 99999s means infinity in such a case.

[Daniel0]

Since when will posting incorrect information help the person who doesn't understand it?

[Azu]

Nevermind... I'm not going to argue with someone who tries to misinterprate me on purpose.

 

:/