jsimpson / binary_reader

A Deno module and helper class that provides an easy way to read different types from a binary array buffer.

Binary Reader

A Deno module helper class that wraps around DataView to provide an easy way to read different types from a binary array buffer while maintaining the current buffer position.

Usage

import { BinaryReader } from "https://deno.land/x/[email protected]/mod.ts";

const filename = "some-file.bin";
const file = Deno.openSync(filename);
const buffer = Deno.readAllSync(file);
Deno.close(file.rid);

const binaryReader = new BinaryReader(buffer);
let data = binaryReader.readUint8();

binary_reader's Issues

TS2729 [ERROR]: Property 'buffer' is used before its initialization.

When using binary_reader, I got the following error from TypeScript:

error: TS2729 [ERROR]: Property 'buffer' is used before its initialization.
    this.buffer.buffer,
         ~~~~~~
    at https://deno.land/x/[email protected]/binary_reader.ts:3:10      

    'buffer' is declared here.
      constructor(private buffer: Uint8Array) {}
                  ~~~~~~~~~~~~~~~~~~~~~~~~~~
        at https://deno.land/x/[email protected]/binary_reader.ts:9:15

TS2729 [ERROR]: Property 'buffer' is used before its initialization.
    this.buffer.byteOffset,
         ~~~~~~
    at https://deno.land/x/[email protected]/binary_reader.ts:4:10

    'buffer' is declared here.
      constructor(private buffer: Uint8Array) {}
        at https://deno.land/x/[email protected]/binary_reader.ts:9:15

TS2729 [ERROR]: Property 'buffer' is used before its initialization.
    this.buffer.byteLength,
         ~~~~~~
    at https://deno.land/x/[email protected]/binary_reader.ts:5:10

    'buffer' is declared here.
      constructor(private buffer: Uint8Array) {}
                  ~~~~~~~~~~~~~~~~~~~~~~~~~~
        at https://deno.land/x/[email protected]/binary_reader.ts:9:15

Found 3 errors.

The problem is that the code to create dataBuffer, is being run before the constructor, and therefore before buffer is initialised.

Link to the code

I have created a pull request with a fix: #1

This is my first time making a pull request, so if there's anything in the process that I've done wrong, please let me know.