(a) Regex CRASH Course! (Pt. 1)

[prometheuzz]

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Character         Matching
 
. (dot)           ANY single character at all
 

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Modifier         Effect
 
s                Ignore whitespace
 

Note that the above is not quite true.

The dot metacharacter does match any single character except for newlines.

I don't know exactly what you mean by 's modifier ignores whitespace'? Anyway, the s modifier just changes the meaning of the dot metacharacter which will then match newlines as well. Agree?

You're right of course Geert. Note that the author's "ignores white space (in the regex)" remark should belong to the x-modifier.

Some more inaccuracies:

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\d, \s etc are what we refer to as "metacharacters"

Should be '\d, \s etc are what we refer to as "short hand character classes"'. Meta characters are: ., *, (, {, [, etc.
\d is a shorthand for [0-9], and [0-9] is a character class (or character set), hence: "short hand character class".

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\w Any single alphanumeric character (a-z, 0-9) and underscores

Should be: "\w Any single alphanumeric character (a-z, A-Z, 0-9) and underscores"

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[x-y] Any single character in the range x to z (e.g. [A-Z])

A typo, I presume: this should be "[x-y] Any single character in the range x to y (e.g. [A-Z])"

[prometheuzz]

This is a great tutorial. I refer to it all the time.

However I think I've found one slight inaccuracy regarding the s modifier which could be updated.

...

Geert already mentioned that. But I don't think this tutorial is updated anymore since is has last been updated in 2005...

[alex.barylski]

Chris...this is probably the best regex resource I have ever found...I refer to this more than anything when it comes to regex...

The only exception would be when I had to support Unicode...have you considered re-writting it to cover Unicode techniques?

Here is a useful resource I have also used several times:

http://www.regular-expressions.info/unicode.html

Cheers,
Alex

[prometheuzz]

Chris...this is probably the best regex resource I have ever found...I refer to this more than anything when it comes to regex...

It would have been better if the errors were removed from it.

Here is a useful resource I have also used several times:

http://www.regular-expressions.info/unicode.html

That is a better resource, IMHO.

[soul_fly]

simply awesome tutorial. I need that earlier.

[remshad]

This is a great tutorial. I refer to it all the time.

However I think I've found one slight inaccuracy regarding the s modifier which could be updated.

...

Geert already mentioned that. But I don't think this tutorial is updated anymore since is has last been updated in 2005...

definitely i also loved this tutorial ...!

[akhilesh1010]

excellent stuff thanks Chris.

[hybris]

Chris, if i were a girl I'd wanted you as father of my children

Thanks, excellent crash course! Finally I understand (or atleast think I understand) some of how the patterns work. Very helpful!

Cheers