Regular Expression Exclude Word

Question

I'm trying to replace all of the event handling functions whose name is either "eventHandler" or ends with "...EventHandler" to be encapsulated in a common event-handling function which does additional tasks before actually calling a event handler.

In short, I'm trying to do this (in sublime text editor) using the regular expression in find & replace:

loginEventHandler(args, callback) => processEventHandler(loginEventHandler, args, callback)

[ Find ]

(eventHandler|(?!processEventHandler)\w+EventHandler)((.*))

[ Replace ]

processEventHandler($1, $2)

This isn't working as expected. The find is also matching rocessEventHandler . How do I ignore matching the function if the function name is "processEventHandler"?

I tried solutions mentioned in the following questions, but didn't help.

Regular expression to match line that doesn't contain a word?

A regular expression to exclude a word/string

Here is the test result:

Answer 1

Basically, your regex matches a part of the string with process is because the regex is not anchored at the start. If you need to match the strings at the start of a string, use ^. If you plan to just match them inside a larger text, use \b (word boundary).

You can use a regex with a negative lookahead anchored at the leading word boundary:

(?i)(\b(?!process)\w*EventHandler)\(([^)]*)\)

See regex demo

The regex (case-insensitive because of (?i) inline modifier) matches:

• \b - a word boundary
• (?!process) - a negative lookahead that fails a match if the following character sequence is found: \w* - zero or more alphanumeric symbols + EventHandler
• \( - opening parenthesis
• ([^)]*) - zero or more characters other than )
• \) - closing parenthesis