Struct FrozenMapBuilder

pub struct FrozenMapBuilder<W>(/* private fields */);

A builder for creating a frozen map.

Example: build in memory

use h3o::{CellIndex, Resolution};
use h3o_ice::FrozenMapBuilder;

let mut builder = FrozenMapBuilder::memory();
builder.insert(CellIndex::try_from(0x85283473fffffff)?, 42)?;

let index = CellIndex::try_from(0x8a1fb46622dffff)?;
builder.extend_iter(
    index
        .children(Resolution::Six)
        .enumerate()
        .map(|(idx, cell)| (cell, idx as u64)),
)?;

let map = builder.into_map();

Example: stream to file

use h3o::{CellIndex, Resolution};
use h3o_ice::FrozenMapBuilder;
use std::{fs, io};

let mut wtr = io::BufWriter::new(fs::File::create(file_path)?);
let mut builder = FrozenMapBuilder::new(wtr)?;

let index = CellIndex::try_from(0x8a1fb46622dffff)?;
builder.extend_iter(
    index
        .children(Resolution::Six)
        .enumerate()
        .map(|(idx, cell)| (cell, idx as u64)),
)?;

builder.finish()?;

Implementations

impl<W: Write> FrozenMapBuilder<W>

pub fn new(wtr: W) -> Result<Self, BuildError>

Create a builder that builds a map by writing it to wtr in a streaming fashion.

Errors

If there was a problem writing to the underlying writer, an error is returned.

pub fn insert(&mut self, index: CellIndex, value: u64) -> Result<(), BuildError>

Insert a new key-value pair into the map.

Errors

If a cell index is inserted that is less than any previous cell index added, then an error is returned. Similarly, if there was a problem writing to the underlying writer, an error is returned.

pub fn extend_iter( &mut self, iter: impl IntoIterator<Item = (CellIndex, u64)>, ) -> Result<(), BuildError>

Calls insert on each cell index in the iterator.

If an error occurred while adding an element, processing is stopped and the error is returned.

Errors

If an error occurred while adding an element, processing is stopped and the error is returned.

pub fn finish(self) -> Result<(), BuildError>

Finishes the construction of the map and flushes the underlying writer. After completion, the data written to W may be read using one of FrozenMap’s constructor methods.

Errors

Returns an error if there was a problem writing to the underlying writer.

pub fn into_inner(self) -> Result<W, BuildError>

Just like finish, except it returns the underlying writer after flushing it.

Errors

Returns an error if there was a problem writing to the underlying writer.

impl FrozenMapBuilder<Vec<u8>>

pub fn memory() -> Self

Create a builder that builds a map in memory.

pub fn into_map(self) -> FrozenMap<Vec<u8>>

Finishes the construction of the map and returns it.