risingwave_common/types/
macros.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
// Copyright 2024 RisingWave Labs
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

/// `for_all_variants` includes all variants of our type system. If you introduced a new array type
/// (also known as scalar type or physical type), be sure to add a variant here.
///
/// It is used to simplify the boilerplate code of repeating all array types, while each type
/// has exactly the same code.
///
/// Take `Utf8` as an example, the layout of the variant is:
/// - `$data_type: Varchar` data type variant name, e.g. `DataType::Varchar`
/// - `$variant_name: Utf8` array type variant name, e.g. `ArrayImpl::Utf8`, `ScalarImpl::Utf8`
/// - `$suffix_name: utf8` the suffix of some functions, e.g. `ArrayImpl::as_utf8`
/// - `$scalar: Box<str>` the scalar type, e.g. `ScalarImpl::Utf8(Box<str>)`
/// - `$scalar_ref: &'scalar str` the scalar reference type, e.g. `ScalarRefImpl::Utf8(&'scalar
///   str)`
/// - `$array: Utf8Array` the array type, e.g. `ArrayImpl::Utf8(Utf8Array)`
/// - `$builder: Utf8ArrayBuilder` the array builder type, e.g.
///   `ArrayBuilderImpl::Utf8(Utf8ArrayBuilder)`
///
/// To use it, one need to provide another macro which accepts arguments in the layout described
/// above. Refer to the following implementations as examples.
///
/// **Note**: See also `dispatch_xx_variants` and `dispatch_data_types` which doesn't require
/// another macro for the implementation and can be easier to use in most cases.
#[macro_export]
macro_rules! for_all_variants {
    ($macro:ident $(, $x:tt)*) => {
        $macro! {
            $($x, )*
            //data_type     variant_name  suffix_name   scalar                      scalar_ref                          array                               builder
            { Int16,        Int16,        int16,        i16,                        i16,                                $crate::array::I16Array,            $crate::array::I16ArrayBuilder          },
            { Int32,        Int32,        int32,        i32,                        i32,                                $crate::array::I32Array,            $crate::array::I32ArrayBuilder          },
            { Int64,        Int64,        int64,        i64,                        i64,                                $crate::array::I64Array,            $crate::array::I64ArrayBuilder          },
            { Int256,       Int256,       int256,       $crate::types::Int256,      $crate::types::Int256Ref<'scalar>,  $crate::array::Int256Array,         $crate::array::Int256ArrayBuilder       },
            { Float32,      Float32,      float32,      $crate::types::F32,         $crate::types::F32,                 $crate::array::F32Array,            $crate::array::F32ArrayBuilder          },
            { Float64,      Float64,      float64,      $crate::types::F64,         $crate::types::F64,                 $crate::array::F64Array,            $crate::array::F64ArrayBuilder          },
            { Varchar,      Utf8,         utf8,         Box<str>,                   &'scalar str,                       $crate::array::Utf8Array,           $crate::array::Utf8ArrayBuilder         },
            { Boolean,      Bool,         bool,         bool,                       bool,                               $crate::array::BoolArray,           $crate::array::BoolArrayBuilder         },
            { Decimal,      Decimal,      decimal,      $crate::types::Decimal,     $crate::types::Decimal,             $crate::array::DecimalArray,        $crate::array::DecimalArrayBuilder      },
            { Interval,     Interval,     interval,     $crate::types::Interval,    $crate::types::Interval,            $crate::array::IntervalArray,       $crate::array::IntervalArrayBuilder     },
            { Date,         Date,         date,         $crate::types::Date,        $crate::types::Date,                $crate::array::DateArray,           $crate::array::DateArrayBuilder         },
            { Time,         Time,         time,         $crate::types::Time,        $crate::types::Time,                $crate::array::TimeArray,           $crate::array::TimeArrayBuilder         },
            { Timestamp,    Timestamp,    timestamp,    $crate::types::Timestamp,   $crate::types::Timestamp,           $crate::array::TimestampArray,      $crate::array::TimestampArrayBuilder    },
            { Timestamptz,  Timestamptz,  timestamptz,  $crate::types::Timestamptz, $crate::types::Timestamptz,         $crate::array::TimestamptzArray,    $crate::array::TimestamptzArrayBuilder  },
            { Jsonb,        Jsonb,        jsonb,        $crate::types::JsonbVal,    $crate::types::JsonbRef<'scalar>,   $crate::array::JsonbArray,          $crate::array::JsonbArrayBuilder        },
            { Serial,       Serial,       serial,       $crate::types::Serial,      $crate::types::Serial,              $crate::array::SerialArray,         $crate::array::SerialArrayBuilder       },
            { Struct,       Struct,       struct,       $crate::types::StructValue, $crate::types::StructRef<'scalar>,  $crate::array::StructArray,         $crate::array::StructArrayBuilder       },
            { List,         List,         list,         $crate::types::ListValue,   $crate::types::ListRef<'scalar>,    $crate::array::ListArray,           $crate::array::ListArrayBuilder         },
            { Map,          Map,          map,          $crate::types::MapValue,    $crate::types::MapRef<'scalar>,     $crate::array::MapArray,            $crate::array::MapArrayBuilder         },
            { Bytea,        Bytea,        bytea,        Box<[u8]>,                  &'scalar [u8],                      $crate::array::BytesArray,          $crate::array::BytesArrayBuilder        }
        }
    };
}

/// Helper macro for expanding type aliases and constants. Internally used by `dispatch_` macros.
#[macro_export]
macro_rules! do_expand_alias {
    ($array:ty, $variant_name:ident, (
        $(Array, $array_alias:ident,)?
        $(ArrayBuilder, $array_builder_alias:ident,)?
        $(Scalar, $scalar_alias:ident,)?
        $(ScalarRef, $scalar_ref_alias:ident,)?
        $(VARIANT_NAME, $variant_name_alias:ident,)?
    )) => {
        $(type $array_alias = $array;)?
        $(type $array_builder_alias = <$array as $crate::array::Array>::Builder;)?
        $(type $scalar_alias = <$array as $crate::array::Array>::OwnedItem;)?
        $(type $scalar_ref_alias<'scalar> = <$array as $crate::array::Array>::RefItem<'scalar>;)?
        $(const $variant_name_alias: &'static str = stringify!($variant_name);)?
    };
}

/// Helper macro for generating dispatching code. Internally used by `dispatch_xx_variants` macros.
#[macro_export(local_inner_macros)]
macro_rules! do_dispatch_variants {
    // Use `tt` for `$alias` as a workaround of nested repetition.
    ($impl:expr, $type:ident, $inner:pat, [$alias:tt], $body:tt, $( { $data_type:ident, $variant_name:ident, $suffix_name:ident, $scalar:ty, $scalar_ref:ty, $array:ty, $builder:ty } ),*) => {
        match $impl {
            $( $type::$variant_name($inner) => {
                do_expand_alias!($array, $variant_name, $alias);
                #[allow(unused_braces)]
                $body
            }, )*
        }
    };
}

/// Dispatch the code block to all variants of `ArrayImpl`.
///
/// # Usage
///
/// The basic usage to access the inner concrete `impl Array` value is:
///
/// ```ignore
/// fn do_stuff<A: Array>(array: &A) { .. }
///
/// fn do_stuff_dispatch(array_impl: &ArrayImpl) {
///     dispatch_array_variants!(array_impl, array, {
///         do_stuff(array)
///     })
/// }
/// ```
///
/// One can also bind the inner concrete `impl Array` type to an alias:
///
/// ```ignore
/// fn do_stuff<A: Array>() { .. }
///
/// fn do_stuff_dispatch(array_impl: &ArrayImpl) {
///     dispatch_array_variants!(array_impl, [A = Array], {
///         do_stuff::<A>()
///     })
/// }
/// ```
///
/// There're more to bind, including type aliases of associated `ArrayBuilder`, `Scalar`, and
/// `ScalarRef`, or even the constant string of the variant name `VARIANT_NAME`. This can be
/// achieved by writing one or more of them in the square brackets. Due to the limitation of macro,
/// the order of the bindings matters.
///
/// ```ignore
/// fn do_stuff_dispatch(array_impl: &ArrayImpl) {
///     dispatch_array_variants!(
///         array_impl,
///         [A = Array, B = ArrayBuilder, S = Scalar, R = ScalarRef, N = VARIANT_NAME],
///         { .. }
///     )
/// }
/// ```
///
/// Alias bindings can also be used along with the inner value accessing:
///
/// ```ignore
/// fn do_stuff<A: Array>(array: &A) { .. }
///
/// fn do_stuff_dispatch(array_impl: &ArrayImpl) {
///     dispatch_array_variants!(array_impl, array, [A = Array], {
///         do_stuff::<A>(array)
///     })
/// }
/// ```
#[macro_export(local_inner_macros)]
macro_rules! dispatch_array_variants {
    ($impl:expr, [$($k:ident = $v:ident),*], $body:tt) => {
        dispatch_array_variants!($impl, _, [$($k = $v),*], $body)
    };
    ($impl:expr, $inner:pat, $body:tt) => {
        dispatch_array_variants!($impl, $inner, [], $body)
    };
    // Switch the order of alias bindings to avoid ambiguousness.
    ($impl:expr, $inner:pat, [$($k:ident = $v:ident),*], $body:tt) => {{
        use $crate::array::ArrayImpl;
        for_all_variants! { do_dispatch_variants, $impl, ArrayImpl, $inner, [($($v, $k,)*)], $body }
    }};
}

/// Dispatch the code block to all variants of `ArrayBuilderImpl`.
///
/// Refer to [`dispatch_array_variants`] for usage.
// TODO: avoid duplication by `macro_metavar_expr` feature
#[macro_export(local_inner_macros)]
macro_rules! dispatch_array_builder_variants {
    ($impl:expr, [$($k:ident = $v:ident),*], $body:tt) => {
        dispatch_array_builder_variants!($impl, _, [$($k = $v),*], $body)
    };
    ($impl:expr, $inner:pat, $body:tt) => {
        dispatch_array_builder_variants!($impl, $inner, [], $body)
    };
    ($impl:expr, $inner:pat, [$($k:ident = $v:ident),*], $body:tt) => {{
        use $crate::array::ArrayBuilderImpl;
        for_all_variants! { do_dispatch_variants, $impl, ArrayBuilderImpl, $inner, [($($v, $k,)*)], $body }
    }};
}

/// Dispatch the code block to all variants of `ScalarImpl`.
///
/// Refer to [`dispatch_array_variants`] for usage.
// TODO: avoid duplication by `macro_metavar_expr` feature
#[macro_export(local_inner_macros)]
macro_rules! dispatch_scalar_variants {
    ($impl:expr, [$($k:ident = $v:ident),*], $body:tt) => {
        dispatch_scalar_variants!($impl, _, [$($k = $v),*], $body)
    };
    ($impl:expr, $inner:pat, $body:tt) => {
        dispatch_scalar_variants!($impl, $inner, [], $body)
    };
    ($impl:expr, $inner:pat, [$($k:ident = $v:ident),*], $body:tt) => {{
        use $crate::types::ScalarImpl;
        for_all_variants! { do_dispatch_variants, $impl, ScalarImpl, $inner, [($($v, $k,)*)], $body }
    }};
}

/// Dispatch the code block to all variants of `ScalarRefImpl`.
///
/// Refer to [`dispatch_array_variants`] for usage.
// TODO: avoid duplication by `macro_metavar_expr` feature
#[macro_export(local_inner_macros)]
macro_rules! dispatch_scalar_ref_variants {
    ($impl:expr, [$($k:ident = $v:ident),*], $body:tt) => {
        dispatch_scalar_ref_variants!($impl, _, [$($k = $v),*], $body)
    };
    ($impl:expr, $inner:pat, $body:tt) => {
        dispatch_scalar_ref_variants!($impl, $inner, [], $body)
    };
    ($impl:expr, $inner:pat, [$($k:ident = $v:ident),*], $body:tt) => {{
        use $crate::types::ScalarRefImpl;
        for_all_variants! { do_dispatch_variants, $impl, ScalarRefImpl, $inner, [($($v, $k,)*)], $body }
    }};
}

/// Helper macro for generating dispatching code. Internally used by `dispatch_data_types` macros.
#[macro_export(local_inner_macros)]
macro_rules! do_dispatch_data_types {
    ($impl:expr, [$alias:tt], $body:tt, $( { $data_type:ident, $variant_name:ident, $suffix_name:ident, $scalar:ty, $scalar_ref:ty, $array:ty, $builder:ty } ),*) => {
        match $impl {
            $( $crate::types::DataType::$data_type { .. } => {
                do_expand_alias!($array, $variant_name, $alias);
                #[allow(unused_braces)]
                $body
            }, )*
        }
    };
}

/// Dispatch the code block to all variants of `DataType`.
///
/// There's no inner value to access, so only alias bindings are supported. Refer to
/// [`dispatch_array_variants`] for usage.
#[macro_export(local_inner_macros)]
macro_rules! dispatch_data_types {
    ($impl:expr, [$($k:ident = $v:ident),*], $body:tt) => {
        for_all_variants! { do_dispatch_data_types, $impl, [($($v, $k,)*)], $body }
    };
}