MikeMcl
Implement polyfill for TC39 bigdecimal
See: https://github.com/tc39/proposal-decimal/issues/17 (polyfill)
and: https://github.com/tc39/proposal-decimal/issues/18 (babel)
Okay, here's a preliminary polyfill implemented from a severely hacked decimal.js:
The API is as described at the TC39 Decimal proposal and the Decimal: For Stage 1 slideshow.
The zip file contains an ES module version and an ES 3+ compatible UMD version.,
Example usage:
import BigDecimal from './bigdecimal.min.mjs';
let a, b, c, options;
a = BigDecimal(0.1);
b = BigDecimal('0.1');
console.log( a['==='](b) ) // false
console.log(a.toString()); // '0.1000000000000000055511151231257827021181583404541015625'
console.log(b.toString()); // '0.1'
console.log( a['!=='](b) ); // true
console.log( a['=='](b) ); // false
console.log( a['!='](b) ); // true
console.log( a['>'](b) ); // true
console.log( a['>='](b) ); // true
console.log( a['<'](b) ); // false
console.log( a['<='](b) ); // false
console.log( a['+'](b).toString() ); // '0.2000000000000000055511151231257827021181583404541015625'
c = a['-'](b);
console.log( c.toString() ); // '5.5511151231257827021181583404541015625e-18'
console.log( c.toFixed() ); // '0.0000000000000000055511151231257827021181583404541015625'
console.log( a['*'](b).toString() ); // '0.01000000000000000055511151231257827021181583404541015625'
a = BigDecimal('34.63');
b = BigDecimal('2.2343465');
c = BigDecimal(b);
console.log( b['==='](c) );
console.log( a['%'](b).toString() );
options = { maximumSignificantDigits: 20, roundingMode: BigDecimal.ROUND_HALF_UP };
console.log( BigDecimal.add(a, b, options).toString() );
console.log( BigDecimal.sub(a, b, options).toString() );
console.log( BigDecimal.mul(a, b, options).toString() );
console.log( BigDecimal.div(a, b, options).toString() );
console.log( BigDecimal.mod(a, b, options).toString() );
console.log( BigDecimal.pow(a, BigDecimal(11), options).toString() );
options = { maximumFractionDigits: 2, roundingMode: BigDecimal.ROUND_UP };
console.log( BigDecimal.round(a, options).toString() );
console.log( b.toExponential() );
console.log( b.toExponential(4, { roundingMode: BigDecimal.ROUND_HALF_UP }) );
console.log( b.toFixed(4, { roundingMode: BigDecimal.ROUND_HALF_UP }) );
console.log( b.toPrecision(4, { roundingMode: BigDecimal.ROUND_HALF_UP }) );
I haven't implemented a BigDecimal.partition method as it seems an odd inclusion and its behaviour was not adequately specified.
Yes, I have a non-minified version. I don't want to expose it before I've had a chance to clean it up a bit.