I want to use bignumber.js in kotlin. Import: ``...

# javascript

[Ran]

I want to use bignumber.js in kotlin.

Import:

val jsMain by getting {
            dependencies {
                implementation(npm("bignumber.js", "9.0.2"))
            }
        }

Declaration:

@JsModule("bignumber.js")
@JsNonModule
external class BigNumber(raw: String) {

    companion object {
        var ROUND_UP: Number /* 0 */
        var ROUND_DOWN: Number /* 1 */
        var ROUND_CEIL: Number /* 2 */
        var ROUND_FLOOR: Number /* 3 */
        var ROUND_HALF_UP: Number /* 4 */
        var ROUND_HALF_DOWN: Number /* 5 */
        var ROUND_HALF_EVEN: Number /* 6 */
        var ROUND_HALF_CEIL: Number /* 7 */
        var ROUND_HALF_FLOOR: Number /* 8 */

        fun config(): Config
        fun set(obj: Config): Config
        fun clone(obj: Config = definedExternally): Any
    }

    interface Config {
        var DECIMAL_PLACES: Number?
            get() = definedExternally
            set(value) = definedExternally
        var ROUNDING_MODE: Number? /* 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 */
            get() = definedExternally
            set(value) = definedExternally
        var EXPONENTIAL_AT: dynamic /* Number? | JsTuple<Number, Number> */
            get() = definedExternally
            set(value) = definedExternally
        var RANGE: dynamic /* Number? | JsTuple<Number, Number> */
            get() = definedExternally
            set(value) = definedExternally
        var CRYPTO: Boolean?
            get() = definedExternally
            set(value) = definedExternally
        var MODULO_MODE: Number? /* 0 | 1 | 3 | 6 | 9 */
            get() = definedExternally
            set(value) = definedExternally
        var POW_PRECISION: Number?
            get() = definedExternally
            set(value) = definedExternally
        var FORMAT: Format?
            get() = definedExternally
            set(value) = definedExternally
        var ALPHABET: String?
            get() = definedExternally
            set(value) = definedExternally
    }

    interface Format {
        var prefix: String?
            get() = definedExternally
            set(value) = definedExternally
        var decimalSeparator: String?
            get() = definedExternally
            set(value) = definedExternally
        var groupSeparator: String?
            get() = definedExternally
            set(value) = definedExternally
        var groupSize: Number?
            get() = definedExternally
            set(value) = definedExternally
        var secondaryGroupSize: Number?
            get() = definedExternally
            set(value) = definedExternally
        var fractionGroupSeparator: String?
            get() = definedExternally
            set(value) = definedExternally
        var fractionGroupSize: Number?
            get() = definedExternally
            set(value) = definedExternally
        var suffix: String?
            get() = definedExternally
            set(value) = definedExternally
    }

    fun plus(number: BigNumber): BigNumber
    fun minus(number: BigNumber): BigNumber
    fun multipliedBy(number: BigNumber): BigNumber
    fun dividedBy(number: BigNumber): BigNumber
    fun modulo(number: BigNumber): BigNumber
    fun comparedTo(number: BigNumber): Number?
    fun toString(base: Int): String
}

Other methods work well except set and clone .

@Test
    fun testConfig() {
        println(BigNumber.config().DECIMAL_PLACES)
        BigNumber.set(object : BigNumber.Config {
            override var DECIMAL_PLACES: Number? = 3
        })
        println(BigNumber.config().DECIMAL_PLACES)
    }

the set method has no effect. The output is like the following:

> Task :jsBrowserTest
[log] 20
[log] 20

Is there anyone can tell me why the set method doesn't work and how can I use clone method?

[Big Chungus]

Can you post how their code looks like in ts/js?

[Ran]

https://github.com/MikeMcl/bignumber.js/blob/master/bignumber.js

[Ran]

Here

[Big Chungus]

Jesus... That one messy js... Better look here - set is declared as static

[Ran]

I declare the set method in companion object , is it wrong?

[Big Chungus]

I think the problem is that you're passing in non-external anonymous object value here

BigNumber.set(object : BigNumber.Config {
            override var DECIMAL_PLACES: Number? = 3
        })

Try constructing Config via js api

js("{}").unsafeCast<Config>().apply {
  ...
}

[Ran]

Wow, it works, thanks so much.

[Ran]

Another question: in JS, clone method will return a new constructor to create BigNumber with specific BigNumber. In Kotlin, how can I use clone ?

[Big Chungus]

fun clone(obj: Config = definedExternally): dynamic is the easies way around. To make it typesafe you could try

fun clone(obj: Config = definedExternally): (BugNumber.Value, Number?) -> BigNumber

Note how you miss out on being able to specify constructor arg names and default values. Unfortunatelly this is not supported in lambda type declarations

[Ran]

Ok, thanks so much, I’ll try it later