Bones/node_modules/vlq/dist/vlq.js

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2017-05-17 13:45:25 -04:00
(function (global, factory) {
typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
typeof define === 'function' && define.amd ? define(['exports'], factory) :
(factory((global.vlq = global.vlq || {})));
}(this, (function (exports) { 'use strict';
var charToInteger = {};
var integerToChar = {};
'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/='.split( '' ).forEach( function ( char, i ) {
charToInteger[ char ] = i;
integerToChar[ i ] = char;
});
function decode ( string ) {
var result = [];
var shift = 0;
var value = 0;
for ( var i = 0; i < string.length; i += 1 ) {
var integer = charToInteger[ string[i] ];
if ( integer === undefined ) {
throw new Error( 'Invalid character (' + string[i] + ')' );
}
var hasContinuationBit = integer & 32;
integer &= 31;
value += integer << shift;
if ( hasContinuationBit ) {
shift += 5;
} else {
var shouldNegate = value & 1;
value >>= 1;
result.push( shouldNegate ? -value : value );
// reset
value = shift = 0;
}
}
return result;
}
function encode ( value ) {
var result;
if ( typeof value === 'number' ) {
result = encodeInteger( value );
} else {
result = '';
for ( var i = 0; i < value.length; i += 1 ) {
result += encodeInteger( value[i] );
}
}
return result;
}
function encodeInteger ( num ) {
var result = '';
if ( num < 0 ) {
num = ( -num << 1 ) | 1;
} else {
num <<= 1;
}
do {
var clamped = num & 31;
num >>= 5;
if ( num > 0 ) {
clamped |= 32;
}
result += integerToChar[ clamped ];
} while ( num > 0 );
return result;
}
exports.decode = decode;
exports.encode = encode;
Object.defineProperty(exports, '__esModule', { value: true });
})));