# `HL7v2.Type.IS`
[🔗](https://github.com/Balneario-de-Cofrentes/hl7v2/blob/v3.10.1/lib/hl7v2/type/is.ex#L1)

Coded Value for User-Defined Tables (IS) -- HL7v2 primitive data type.

Lossless storage: the value is stored and returned as a plain binary string.
The HL7 spec constrains IS values to site-defined (user-defined) tables, but
this implementation does not enforce table membership — any string is accepted.

# `encode`

```elixir
@spec encode(binary() | nil) :: binary()
```

Encodes an IS value. Returns the string as-is, or empty string for nil.

## Examples

    iex> HL7v2.Type.IS.encode("ICU")
    "ICU"

    iex> HL7v2.Type.IS.encode(nil)
    ""

# `parse`

```elixir
@spec parse(binary() | nil) :: binary() | nil
```

Parses an IS string. Returns the string as-is, or `nil` for empty/nil input.

## Examples

    iex> HL7v2.Type.IS.parse("ICU")
    "ICU"

    iex> HL7v2.Type.IS.parse("")
    nil

    iex> HL7v2.Type.IS.parse(nil)
    nil

---

*Consult [api-reference.md](api-reference.md) for complete listing*