Basics

Use this website interactively to learn. Use this website to generate regular expressions

Exclude something

Use [^something] to exclude some patterns.

Include something

Similar to excluding but [something].

Include one or another

[one|another]

Repeats

1. * 0 or more of something
2. + 1 or more of something

Some Characters

1. . Everything except new line.

in or der to search for [](.org) you need to write \[\[.*\]\]. Let’s say you want to keep the content between the brackets. Then you need to use capture groups and instead you add a pair of parantheses which acts as a group and then you can reference to it. \[\[(.*)\]\] Then you can reference to it by $1. $0 is the whole pattern you searched for. So if you replace your search with $0 it basically doesn’t change anything.

Example

You want to convert [anything](anything.org) to [anything](anything.md). you can simply search for \[\[([^\]]*)\]\] and then replace it by [$1]($1.md) since you only have 1 capture group.

We have to exlude bracket characters by [^\]]* which means everything except ], [ can be repeated unlimited in the group 1 to avoid selecting something lik [anv](anv.org) blah blah [bcd](bcd.org). \[\[([^\]]*)\]\]