When comparing Nunjucks vs FLAVE, the Slant community recommends Nunjucks for most people. In the question“What are the best JavaScript templating engines?” Nunjucks is ranked 5th while FLAVE is ranked 26th.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Very user friendly
Pro Building blocks for CMS Websites
Another token based system with all of the logic, looping and variable control that other engines provide. But in addition it supports some more advanced page composition elements e.g. block inheritance, includes, layout inheritance, custom tags and macros — all absolutely perfect for a CMS where pages are typically composed of a series of “building blocks”.
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Pro Suppported by Mozilla
Pro Has Jinja2 as role model
Pro Open Source
Pro Syntax Highlighting
Syntax Highlighting extensions for Atom and VSCODE
Pro JavaScript allowed in views
Pro Helper functions
Can write pure JavaScript helper functions to include in the view file.
Pro Multiple Templates in a single file
Optionally encapsulate views within a class as well as have as many view as you want.
Pro Not white space sensitive
Cons
Con Seeking new maintainer
Con Limited support and testing
Con No data binding
Flave only generates HTML.