github.com/matrixorigin/matrixone@v0.7.0/pkg/vm/engine/tae/common/generator.go (about)

     1  // Copyright 2021 Matrix Origin
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package common
    16  
    17  type OffsetT interface {
    18  	int | uint32
    19  }
    20  
    21  type RowGen interface {
    22  	HasNext() bool
    23  	Next() uint32
    24  }
    25  
    26  type RowGenWrapper[T OffsetT] struct {
    27  	Sels []T
    28  	Idx  int
    29  }
    30  
    31  func NewRowGenWrapper[T OffsetT](sels ...T) *RowGenWrapper[T] {
    32  	return &RowGenWrapper[T]{
    33  		Sels: sels,
    34  	}
    35  }
    36  
    37  func (wrapper *RowGenWrapper[T]) HasNext() bool {
    38  	return wrapper.Idx < len(wrapper.Sels)
    39  }
    40  
    41  func (wrapper *RowGenWrapper[T]) Next() uint32 {
    42  	row := wrapper.Sels[wrapper.Idx]
    43  	wrapper.Idx++
    44  	return uint32(row)
    45  }