# snowballstem

This repository contains the Go stemmers generated by the [Snowball](https://github.com/snowballstem/snowball) project.  They are maintained outside of the core bleve package so that they may be more easily be reused in other contexts.

## Usage

All these stemmers export a single `Stem()` method which operates on a snowball `Env` structure.  The `Env` structure maintains all state for the stemmer.  A new `Env` is created to point at an initial string.  After stemming, the results of the `Stem()` operation can be retrieved using the `Current()` method.  The `Env` structure can be reused for subsequent calls by using the `SetCurrent()` method.

## Example

```
package main

import (
	"fmt"

	"github.com/blevesearch/snowballstem"
	"github.com/blevesearch/snowballstem/english"
)

func main() {

	// words to stem
	words := []string{
		"running",
		"jumping",
	}

	// build new environment
	env := snowballstem.NewEnv("")

	for _, word := range words {
		// set up environment for word
		env.SetCurrent(word)
		// invoke stemmer
		english.Stem(env)
		// print results
		fmt.Printf("%s stemmed to %s\n", word, env.Current())
	}
}
```
Produces Output:
```
$ ./snowtest
running stemmed to run
jumping stemmed to jump
```

## Testing

The test harness for these stemmers is hosted in the main [Snowball](https://github.com/snowballstem/snowball) repository.  There are functional tests built around the separate [snowballstem-data](https://github.com/snowballstem/snowball-data) repository, and there is support for fuzz-testing the stemmers there as well.

## Generating the Stemmers

```
$ export SNOWBALL=/path/to/github.com/snowballstem/snowball/after/snowball/built
$ go generate
```

## Updated the Go Generate Commands

A simple tool is provided to automate these from the snowball algorithms directory:

```
$ go run gengen.go /path/to/github.com/snowballstem/snowball/algorithms
```