vue hello world项目
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// @flow
import { write, read } from "@xtuc/ieee754";
/**
* According to https://webassembly.github.io/spec/binary/values.html#binary-float
* n = 32/8
*/
export const NUMBER_OF_BYTE_F32 = 4;
/**
* According to https://webassembly.github.io/spec/binary/values.html#binary-float
* n = 64/8
*/
export const NUMBER_OF_BYTE_F64 = 8;
export const SINGLE_PRECISION_MANTISSA = 23;
export const DOUBLE_PRECISION_MANTISSA = 52;
export function encodeF32(v: number): Array<number> {
const buffer = [];
write(buffer, v, 0, true, SINGLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F32);
return buffer;
}
export function encodeF64(v: number): Array<number> {
const buffer = [];
write(buffer, v, 0, true, DOUBLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F64);
return buffer;
}
export function decodeF32(bytes: Array<Byte>): number {
const buffer = Buffer.from(bytes);
return read(buffer, 0, true, SINGLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F32);
}
export function decodeF64(bytes: Array<Byte>): number {
const buffer = Buffer.from(bytes);
return read(buffer, 0, true, DOUBLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F64);
}