@kamino-finance/klend-sdk
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Typescript SDK for interacting with the Kamino Lending (klend) protocol
72 lines • 2.9 kB
JavaScript
;
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.ZERO_FRACTION = exports.Fraction = void 0;
exports.bfToDecimal = bfToDecimal;
const bn_js_1 = __importDefault(require("bn.js"));
const decimal_js_1 = __importDefault(require("decimal.js"));
const utils_1 = require("./utils");
class Fraction {
static MAX_SIZE_F = 128;
static MAX_SIZE_BF = 256;
static FRACTIONS = 60;
static MULTIPLIER = new decimal_js_1.default(2).pow(Fraction.FRACTIONS);
static MAX_F_BN = new bn_js_1.default(2).pow(new bn_js_1.default(Fraction.MAX_SIZE_F)).sub(new bn_js_1.default(1));
static MAX_BF_BN = new bn_js_1.default(2).pow(new bn_js_1.default(Fraction.MAX_SIZE_BF)).sub(new bn_js_1.default(1));
static MIN_BN = new bn_js_1.default(0);
valueSf;
constructor(valueSf) {
if (valueSf.lt(Fraction.MIN_BN) || valueSf.gt(Fraction.MAX_BF_BN)) {
throw new Error('Number out of range');
}
this.valueSf = valueSf;
}
toDecimal() {
return new decimal_js_1.default(this.valueSf.toString()).div(Fraction.MULTIPLIER);
}
static fromDecimal(n) {
const scaledDecimal = new decimal_js_1.default(n).mul(Fraction.MULTIPLIER);
const roundedScaledDecimal = (0, utils_1.roundNearest)(scaledDecimal);
// Note: the `Decimal.toString()` can return exponential notation (e.g. "1e9") for large numbers. This notation is
// not accepted by `BN` constructor (i.e. invalid character "e"). Hence, we use `Decimal.toFixed()` (which is
// different than `number.toFixed()` - it will not do any rounding, just render a normal notation).
const scaledValue = new bn_js_1.default(roundedScaledDecimal.toFixed());
return new Fraction(scaledValue);
}
static fromBps(n) {
const decimal = new decimal_js_1.default(n).div(10000);
return Fraction.fromDecimal(decimal);
}
static fromPercent(n) {
const decimal = new decimal_js_1.default(n).div(100);
return Fraction.fromDecimal(decimal);
}
getValue() {
return this.valueSf;
}
gt(x) {
return this.valueSf.gt(x.getValue());
}
lt(x) {
return this.valueSf.lt(x.getValue());
}
gte(x) {
return this.valueSf.gte(x.getValue());
}
lte(x) {
return this.valueSf.lte(x.getValue());
}
eq(x) {
return this.valueSf.eq(x.getValue());
}
}
exports.Fraction = Fraction;
exports.ZERO_FRACTION = new Fraction(new bn_js_1.default(0));
function bfToDecimal(x) {
const bsf = x.value;
const accSf = bsf.reduce((acc, curr, i) => acc.add(curr.shln(i * 64)), new bn_js_1.default(0));
return new Fraction(accSf).toDecimal();
}
//# sourceMappingURL=fraction.js.map