Regular Expressions 101

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Settings

All settings to control the application are located here.

They are automatically saved as you change them and will be automatically loaded every time.

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General

LanguageMax Execution Time

This setting affects how long the matcher will try to match your regex before it decides to give up

Always collapse left sidebarAlways collapse right sidebarShow warning popup when trying to leave site with unsaved dataUse the default behavior for the tab key

The tab key will by default switch to the next field in the tabbing order. If this option is disabled, input areas for regex, substitution and test string will instead consume the tab key.

Theme

Style

This setting adjusts the site-wide theme

Editor

Default flavor

Select the flavor you want to use when the site loads. Note: a saved entry's flavor will override this

Default code generator language

If left to automatic, the code generator will mirror the currently selected flavor in the editor

Highlight Syntax

Enable or disable the syntax highlighting of your regular expression in the editor

Auto-complete BracketsWrap Long LinesShow Line Numbers in Regex EditorShow Line Numbers in Test String Editor and Substitution ResultShow tooltips

Show informative and helpful tooltips when hovering tokens in the regex editor

Visualize whitespace and other special charactersShow how many steps a regular expression takes to evaluate

If you are working on very large and complex expressions, turning this option off will yield improved performance

Include non-participating groups in match result

This setting determines whether groups in your regex, which did not match anything in the subject string, should be included in the results or not

Regular Expressions 101

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