README.md.tpl

# Qualify!

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Library for fast rules evaluation for Go. Qualify is able to quickly match a fact against large number of pre-defined rules.

### Example:

```go
import (
	"fmt"

	"github.com/bsm/qualify"
)

// Fact is an example fact
type Fact struct {
  Country string
  Browser string
  OS      string
  Attrs   []int
}

// Enumeration of our fact features
const (
  FieldCountry qualify.Field = iota
  FieldBrowser
  FieldOS
  FieldAttrs
)

// factReader is a wrapper around facts to
// make them comply with qualify.Fact
type factReader struct {
  Dict qualify.StrDict
  Fact
}

func (r *factReader) AppendFieldValues(x []int, f qualify.Field) []int {
  switch f {
  case FieldCountry:
    return r.Dict.Lookup(x, r.Country)
  case FieldBrowser:
    return r.Dict.Lookup(x, r.Browser)
  case FieldOS:
    return r.Dict.Lookup(x, r.OS)
  case FieldAttrs:
    return append(x, r.Attrs...)
  }
  return x
}

func main() {{ "ExampleQualifier" | code }}
```