# Group SeedExtensionTags
Tags for selecting seed extension algorithm.

## Grouped Tags Overview

- `typedef Tag<GappedXDrop_> const GappedXDrop;`
  Gapped extension of a seed until score drops below a given value; only works for SimpleSeed.
- `typedef Tag<MatchExtend_> const MatchExtend;`
  Extends a seed until a mismatch occurs.
- `typedef Tag<UngappedXDrop_> const UnGappedXDrop;`
  Ungapped extension of a seed until score drops below a given value.

## See Also

- extendSeed

## Grouped Tags Detail

### `typedef Tag<GappedXDrop_> const GappedXDrop;`

Defined in
  <seqan/seeds.h>

Gapped extension of a seed until score drops below a given value; only works for SimpleSeed.

### `typedef Tag<MatchExtend_> const MatchExtend;`

Defined in
  <seqan/seeds.h>

Extends a seed until a mismatch occurs.

### `typedef Tag<UngappedXDrop_> const UnGappedXDrop;`

Defined in
  <seqan/seeds.h>

Ungapped extension of a seed until score drops below a given value.

#### Dox Sources

    /*!
     * @defgroup SeedExtensionTags
     *
     * @brief Tags for selecting seed extension algorithm.
     *
     * @see Seed#extendSeed
     *
     * @tag SeedExtensionTags#MatchExtend
     *
     * @headerfile <seqan/seeds.h>
     *
     * @brief Extends a seed until a mismatch occurs.
     *
     * @signature typedef Tag<MatchExtend_> const MatchExtend;
     *
     * @tag SeedExtensionTags#UnGappedXDrop
     *
     * @headerfile <seqan/seeds.h>
     *
     * @brief Ungapped extension of a seed until score drops below a given value.
     *
     * @signature typedef Tag<UngappedXDrop_> const UnGappedXDrop;
     *
     * @tag SeedExtensionTags#GappedXDrop
     *
     * @headerfile <seqan/seeds.h>
     *
     * @brief Gapped extension of a seed until score drops below a given value; only
     *        works for SimpleSeed.
     *
     * @signature typedef Tag<GappedXDrop_> const GappedXDrop;
     */