Macro connectorx::impl_transport

macro_rules! impl_transport {
    (
        name = $TP:ty,
        error = $ET:ty,
        systems = $TSS:tt => $TSD:tt,
        route = $S:ty => $D:ty,
        mappings = {
            $(
                { $($TOKENS:tt)+ }
            )*
        }
    ) => { ... };
    (@transport $TP:ty, $ET:ty [$TSS:tt, $TSD:tt] [$S:ty, $D:ty] $([ $($TOKENS:tt)+ ])*) => { ... };
    (@cvtts [$TSS:tt, $TSD:tt] $( [$V1:tt [$T1:ty] => $V2:tt [$T2:ty] | conversion $HOW:ident] )*) => { ... };
    (@process [$TSS:tt, $TSD:tt] $([ $V1:tt [$T1:ty] => $V2:tt [$T2:ty] | conversion $HOW:ident ])*) => { ... };
    (@processor [$TSS:tt, $TSD:tt] $([ $V1:tt [$T1:ty] => $V2:tt [$T2:ty] | conversion $HOW:ident ])*, $([ $($TOKENS:tt)+ ])*) => { ... };
    (@process_func_branch $OPT:ident [ $V1:tt [&$L1:lifetime $T1:ty] => $V2:tt [&$L2:lifetime $T2:ty] | conversion $HOW:ident ]) => { ... };
    (@process_func_branch $OPT:ident [ $V1:tt [$T1:ty] => $V2:tt [&$L2:lifetime $T2:ty] | conversion $HOW:ident ]) => { ... };
    (@process_func_branch $OPT:ident [ $V1:tt [&$L1:lifetime $T1:ty] => $V2:tt [$T2:ty] | conversion $HOW:ident ]) => { ... };
    (@process_func_branch $OPT:ident [ $V1:tt [$T1:ty] => $V2:tt [$T2:ty] | conversion $HOW:ident ]) => { ... };
    (@process_func_branch true $T1:ty, $T2:ty) => { ... };
    (@process_func_branch false $T1:ty, $T2:ty) => { ... };
    (@cvt $TP:ty, $V1:tt [$T1:ty] => $V2:tt [$T2:ty] | conversion $HOW:ident) => { ... };
    (@cvt auto $TP:ty, $T1:ty, $T2:ty) => { ... };
    (@cvt auto_vec $TP:ty, $T1:ty, $T2:ty) => { ... };
    (@cvt owned $TP:ty, $T1:ty, $T2:ty) => { ... };
    (@cvt option $TP:ty, $T1:ty, $T2:ty) => { ... };
    (@cvt none $TP:ty, $T1:ty, $T2:ty) => { ... };
}

A macro to help define a Transport.

Example Usage

impl_transport!(
    name = MsSQLArrowTransport,
    error = MsSQLArrowTransportError,
    systems = MsSQLTypeSystem => ArrowTypeSystem,
    route = MsSQLSource => ArrowDestination,
    mappings = {
        { Tinyint[u8]                   => Int32[i32]                | conversion auto }
        { Smallint[i16]                 => Int32[i32]                | conversion auto }
        { Int[i32]                      => Int32[i32]                | conversion auto }
        { Bigint[i64]                   => Int64[i64]                | conversion auto }
        { Intn[IntN]                    => Int64[i64]                | conversion option }
        { Float24[f32]                  => Float32[f32]              | conversion auto }
        { Float53[f64]                  => Float64[f64]              | conversion auto }
        { Floatn[FloatN]                => Float64[f64]              | conversion option }
        { Bit[bool]                     => Boolean[bool]             | conversion auto  }
        { Nvarchar[&'r str]             => LargeUtf8[String]         | conversion owned }
        { Varchar[&'r str]              => LargeUtf8[String]         | conversion none }
        { Nchar[&'r str]                => LargeUtf8[String]         | conversion none }
        { Char[&'r str]                 => LargeUtf8[String]         | conversion none }
        { Text[&'r str]                 => LargeUtf8[String]         | conversion none }
        { Ntext[&'r str]                => LargeUtf8[String]         | conversion none }
        { Binary[&'r [u8]]              => LargeBinary[Vec<u8>]      | conversion owned }
        { Varbinary[&'r [u8]]           => LargeBinary[Vec<u8>]      | conversion none }
        { Image[&'r [u8]]               => LargeBinary[Vec<u8>]      | conversion none }
        { Numeric[Decimal]              => Float64[f64]              | conversion option }
        { Decimal[Decimal]              => Float64[f64]              | conversion none }
        { Datetime[NaiveDateTime]       => Date64[NaiveDateTime]     | conversion auto }
        { Datetime2[NaiveDateTime]      => Date64[NaiveDateTime]     | conversion none }
        { Smalldatetime[NaiveDateTime]  => Date64[NaiveDateTime]     | conversion none }
        { Date[NaiveDate]               => Date32[NaiveDate]         | conversion auto }
        { Datetimeoffset[DateTime<Utc>] => DateTimeTz[DateTime<Utc>] | conversion auto }
        { Uniqueidentifier[Uuid]        => LargeUtf8[String]         | conversion option }
    }
);

This implements a Transport called MsSQLArrowTransport that can convert types from MsSQL to Arrow.