R – Place character right next to regex group reference

regex

How can I place characters directly next to a group reference in regex? For example, if I am replacing the expression "0([0-9])" with "\1 aaa" it will show the number with a space and then "aaa" next to it. I want to place "aaa" directly next to the number without a space in between them.

EDIT: Sorry, I forgot the issue in my example. I am trying to place a number directly next to the group reference, which does not work. I am using the Python re module.

Best Answer

Use \g instead of \n:

 re.sub(r'0([0-9])',r'\g<1>4',"foo02")

For more information: http://docs.python.org/library/re.html#re.sub

Related Solutions

Regex: matching up to the first occurrence of a character

You need

/[^;]*/

The [^;] is a character class, it matches everything but a semicolon.

To cite the perlre manpage:

You can specify a character class, by enclosing a list of characters in [] , which will match any character from the list. If the first character after the "[" is "^", the class matches any character not in the list.

This should work in most regex dialects.

Php – Using PHP and regex, insert a character between a group of matched characters

You don't need to do recursive. If I have understood you correctly, you should be able to do this:

$sku = "AXR900DEF334";
$string = preg_replace('/((?<=[A-Z]{2})(?=[0-9])|(?<=[0-9])(?=[A-Z]{2}))/',' ', $sku);
echo $string;

OUTPUT

AXR 900 DEF 334

This will match both when the letters precedes and comes after the digits.

Best Answer

Related Solutions

Regex: matching up to the first occurrence of a character

Php – Using PHP and regex, insert a character between a group of matched characters

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