(scale: number): (self: BigDecimal) => BigDecimal
(self: BigDecimal, scale?: number): BigDecimalComputes a truncated BigDecimal at the given scale. This removes fractional digits beyond the scale,
rounding toward zero.
When to use
Use when you need to discard fractional digits beyond a scale rather than round half up, half down, or toward an infinity.
Example (Truncating decimals)
import { BigDecimal } from "effect"
console.log(BigDecimal.truncate(BigDecimal.fromStringUnsafe("145"), -1)) // BigDecimal(140)
console.log(BigDecimal.truncate(BigDecimal.fromStringUnsafe("-14.5"))) // BigDecimal(-14)export const const truncate: {
(scale: number): (
self: BigDecimal
) => BigDecimal
(self: BigDecimal, scale?: number): BigDecimal
}
Computes a truncated BigDecimal at the given scale. This removes fractional digits beyond the scale,
rounding toward zero.
When to use
Use when you need to discard fractional digits beyond a scale rather than
round half up, half down, or toward an infinity.
Example (Truncating decimals)
import { BigDecimal } from "effect"
console.log(BigDecimal.truncate(BigDecimal.fromStringUnsafe("145"), -1)) // BigDecimal(140)
console.log(BigDecimal.truncate(BigDecimal.fromStringUnsafe("-14.5"))) // BigDecimal(-14)
truncate: {
(scale: numberscale: number): (self: BigDecimal(parameter) self: {
value: bigint;
scale: number;
normalized: BigDecimal;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
self: BigDecimal) => BigDecimal
(self: BigDecimal(parameter) self: {
value: bigint;
scale: number;
normalized: BigDecimal;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
self: BigDecimal, scale: number | undefinedscale?: number): BigDecimal
} = dual<(...args: Array<any>) => any, (self: BigDecimal, scale?: number) => BigDecimal>(isDataFirst: (args: IArguments) => boolean, body: (self: BigDecimal, scale?: number) => BigDecimal): ((...args: Array<any>) => any) & ((self: BigDecimal, scale?: number) => BigDecimal) (+1 overload)Creates a function that can be called in data-first style or data-last
(pipe-friendly) style.
When to use
Use to expose one implementation through both direct and pipe-friendly
call styles.
Details
Pass either the arity of the uncurried function or a predicate that decides
whether the current call is data-first. Arity is the common case. Use a
predicate when optional arguments make arity ambiguous.
Example (Selecting data-first or data-last style by arity)
import { Function, pipe } from "effect"
const sum = Function.dual<
(that: number) => (self: number) => number,
(self: number, that: number) => number
>(2, (self, that) => self + that)
console.log(sum(2, 3)) // 5
console.log(pipe(2, sum(3))) // 5
Example (Defining overloads with call signatures)
import { Function, pipe } from "effect"
const sum: {
(that: number): (self: number) => number
(self: number, that: number): number
} = Function.dual(2, (self: number, that: number): number => self + that)
console.log(sum(2, 3)) // 5
console.log(pipe(2, sum(3))) // 5
Example (Selecting data-first or data-last style with a predicate)
import { Function, pipe } from "effect"
const sum = Function.dual<
(that: number) => (self: number) => number,
(self: number, that: number) => number
>(
(args) => args.length === 2,
(self, that) => self + that
)
console.log(sum(2, 3)) // 5
console.log(pipe(2, sum(3))) // 5
dual(const isBigDecimalArgs: (
args: IArguments
) => boolean
isBigDecimalArgs, (self: BigDecimal(parameter) self: {
value: bigint;
scale: number;
normalized: BigDecimal;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
self: BigDecimal, scale: numberscale: number = 0): BigDecimal => {
if (self: BigDecimal(parameter) self: {
value: bigint;
scale: number;
normalized: BigDecimal;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
self.BigDecimal.scale: numberscale <= scale: numberscale) {
return self: BigDecimal(parameter) self: {
value: bigint;
scale: number;
normalized: BigDecimal;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
self
}
// BigInt division truncates towards zero
return const make: (
value: bigint,
scale: number
) => BigDecimal
Creates a BigDecimal from a bigint value and a scale.
When to use
Use to construct a decimal directly from its unscaled integer value and
decimal scale.
Example (Creating decimals from bigint and scale)
import { BigDecimal } from "effect"
// Create 123.45 (12345 with scale 2)
const decimal = BigDecimal.make(12345n, 2)
console.log(BigDecimal.format(decimal)) // "123.45"
// Create 42 (42 with scale 0)
const integer = BigDecimal.make(42n, 0)
console.log(BigDecimal.format(integer)) // "42"
make(self: BigDecimal(parameter) self: {
value: bigint;
scale: number;
normalized: BigDecimal;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
self.BigDecimal.value: bigintvalue / (const bigint10: bigintbigint10 ** var BigInt: BigIntConstructor
;(value: bigint | boolean | number | string) =>
bigint
BigInt(self: BigDecimal(parameter) self: {
value: bigint;
scale: number;
normalized: BigDecimal;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
self.BigDecimal.scale: numberscale - scale: numberscale)), scale: numberscale)
})