js/src/enum.ts

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import * as Schema_ from './fb/Schema';
import * as Message_ from './fb/Message';

export import ArrowType = Schema_.org.apache.arrow.flatbuf.Type;
export import DateUnit = Schema_.org.apache.arrow.flatbuf.DateUnit;
export import TimeUnit = Schema_.org.apache.arrow.flatbuf.TimeUnit;
export import Precision = Schema_.org.apache.arrow.flatbuf.Precision;
export import UnionMode = Schema_.org.apache.arrow.flatbuf.UnionMode;
export import IntervalUnit = Schema_.org.apache.arrow.flatbuf.IntervalUnit;
export import MessageHeader = Message_.org.apache.arrow.flatbuf.MessageHeader;
export import MetadataVersion = Schema_.org.apache.arrow.flatbuf.MetadataVersion;

/**
 * Main data type enumeration.
 *
 * Data types in this library are all *logical*. They can be expressed as
 * either a primitive physical type (bytes or bits of some fixed size), a
 * nested type consisting of other data types, or another data type (e.g. a
 * timestamp encoded as an int64).
 *
 * **Note**: Only enum values 0-17 (NONE through Map) are written to an Arrow
 * IPC payload.
 *
 * The rest of the values are specified here so TypeScript can narrow the type
 * signatures further beyond the base Arrow Types. The Arrow DataTypes include
 * metadata like `bitWidth` that impact the type signatures of the values we
 * accept and return.
 *
 * For example, the `Int8Vector` reads 1-byte numbers from an `Int8Array`, an
 * `Int32Vector` reads a 4-byte number from an `Int32Array`, and an `Int64Vector`
 * reads a pair of 4-byte lo, hi 32-bit integers as a zero-copy slice from the
 * underlying `Int32Array`.
 *
 * Library consumers benefit by knowing the narrowest type, since we can ensure
 * the types across all public methods are propagated, and never bail to `any`.
 * These values are _never_ used at runtime, and they will _never_ be written
 * to the flatbuffers metadata of serialized Arrow IPC payloads.
 */
export enum Type {
    /** The default placeholder type */
    NONE            =  0,
    /** A NULL type having no physical storage */
    Null            =  1,
    /** Signed or unsigned 8, 16, 32, or 64-bit little-endian integer */
    Int             =  2,
    /** 2, 4, or 8-byte floating point value */
    Float           =  3,
    /** Variable-length bytes (no guarantee of UTF8-ness) */
    Binary          =  4,
    /** UTF8 variable-length string as List<Char> */
    Utf8            =  5,
    /** Boolean as 1 bit, LSB bit-packed ordering */
    Bool            =  6,
    /** Precision-and-scale-based decimal type. Storage type depends on the parameters. */
    Decimal         =  7,
    /** int32_t days or int64_t milliseconds since the UNIX epoch */
    Date            =  8,
    /** Time as signed 32 or 64-bit integer, representing either seconds, milliseconds, microseconds, or nanoseconds since midnight since midnight */
    Time            =  9,
    /** Exact timestamp encoded with int64 since UNIX epoch (Default unit millisecond) */
    Timestamp       = 10,
    /** YEAR_MONTH or DAY_TIME interval in SQL style */
    Interval        = 11,
    /** A list of some logical data type */
    List            = 12,
    /** Struct of logical types */
    Struct          = 13,
    /** Union of logical types */
    Union           = 14,
    /** Fixed-size binary. Each value occupies the same number of bytes */
    FixedSizeBinary = 15,
    /** Fixed-size list. Each value occupies the same number of bytes */
    FixedSizeList   = 16,
    /** Map of named logical types */
    Map             = 17,

    /** Dictionary aka Category type */
    Dictionary            = -1,
    Int8                  = -2,
    Int16                 = -3,
    Int32                 = -4,
    Int64                 = -5,
    Uint8                 = -6,
    Uint16                = -7,
    Uint32                = -8,
    Uint64                = -9,
    Float16               = -10,
    Float32               = -11,
    Float64               = -12,
    DateDay               = -13,
    DateMillisecond       = -14,
    TimestampSecond       = -15,
    TimestampMillisecond  = -16,
    TimestampMicrosecond  = -17,
    TimestampNanosecond   = -18,
    TimeSecond            = -19,
    TimeMillisecond       = -20,
    TimeMicrosecond       = -21,
    TimeNanosecond        = -22,
    DenseUnion            = -23,
    SparseUnion           = -24,
    IntervalDayTime       = -25,
    IntervalYearMonth     = -26,
}

export enum BufferType {
    /**
     * used in List type, Dense Union and variable length primitive types (String, Binary)
     */
    OFFSET = 0,

    /**
     * actual data, either wixed width primitive types in slots or variable width delimited by an OFFSET vector
     */
    DATA = 1,

    /**
     * Bit vector indicating if each value is null
     */
    VALIDITY = 2,

    /**
     * Type vector used in Union type
     */
    TYPE = 3
  }