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# ``

Writing your own filter is very easy: just register a new filter (injectable) factory function with your module. This factory function should return a new filter function which takes the input value as the first argument. Any filter arguments are passed in as additional arguments to the filter function.

The following sample filter reverses a text string. In addition, it conditionally makes the text upper-case.

### Source

## Demo

## Related Topics

- Understanding Angular Filters
- Angular HTML Compiler

## Related API

- `Angular Filter API`