a2/gist:1196145

## gistfile1.md

      
    Raw
  

              gistfile1.md
            
          
Name
Pattern
Description
Example


Positive Lookahead
q(?=u)
q followed by u
q in absquatulate


Negative Lookahead
q(?!u)
q not followed by u
q in qwerty


Positive Lookbehind
(?<=q)u
u preceded by q
u in question


Negative Lookbehind
(?<!q)u
u not preceded by q
u in excuses
Name	Pattern	Description	Example
Positive Lookahead	`q(?=u)`	`q` followed by `u`	`q` in `absquatulate`
Negative Lookahead	`q(?!u)`	`q` not followed by `u`	`q` in `qwerty`
Positive Lookbehind	`(?<=q)u`	`u` preceded by `q`	`u` in `question`
Negative Lookbehind	`(?<!q)u`	`u` not preceded by `q`	`u` in `excuses`