HaoYang670 opened a new issue, #2311:
URL: https://github.com/apache/arrow-rs/issues/2311
**Is your feature request related to a problem or challenge? Please describe
what you are trying to do.**
There are lots of places in our code when we need to build the data type for
a list array:
```rust
let data_type = if OffsetSize::IS_LARGE {
DataType::LargeList(field)
} else {
DataType::List(field)
};
```
We judge the `OffsetSize` at runtime (I am not sure whether the LLVM could
do constant folding on it), however, this computation could be done at compile
time.
**Describe the solution you'd like**
Add a constant value for List array:
```rust
const DATA_TYPE_CONSTRUCTOR: fn(Box<Field>) -> DataType =
if OffsetSize::IS_LARGE { DataType::LargeList} else {DataType::List}
```
Then we can simplify the code to get the data type at runtime:
```rust
let data_type = Self::DATA_TYPE_CONSTRUCTOR(field);
```
**Describe alternatives you've considered**
We could not do this.
**Additional context**
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