| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526 | /** *  The **FixedNumber** class permits using values with decimal places, *  using fixed-pont math. * *  Fixed-point math is still based on integers under-the-hood, but uses an *  internal offset to store fractional components below, and each operation *  corrects for this after each operation. * *  @_section: api/utils/fixed-point-math:Fixed-Point Maths  [about-fixed-point-math] */import { getBytes } from "./data.js";import { assert, assertArgument, assertPrivate } from "./errors.js";import { getBigInt, getNumber, fromTwos, mask, toBigInt } from "./maths.js";import { defineProperties } from "./properties.js";const BN_N1 = BigInt(-1);const BN_0 = BigInt(0);const BN_1 = BigInt(1);const BN_5 = BigInt(5);const _guard = {};// Constant to pull zeros from for multiplierslet Zeros = "0000";while (Zeros.length < 80) {    Zeros += Zeros;}// Returns a string "1" followed by decimal "0"sfunction getTens(decimals) {    let result = Zeros;    while (result.length < decimals) {        result += result;    }    return BigInt("1" + result.substring(0, decimals));}function checkValue(val, format, safeOp) {    const width = BigInt(format.width);    if (format.signed) {        const limit = (BN_1 << (width - BN_1));        assert(safeOp == null || (val >= -limit && val < limit), "overflow", "NUMERIC_FAULT", {            operation: safeOp, fault: "overflow", value: val        });        if (val > BN_0) {            val = fromTwos(mask(val, width), width);        }        else {            val = -fromTwos(mask(-val, width), width);        }    }    else {        const limit = (BN_1 << width);        assert(safeOp == null || (val >= 0 && val < limit), "overflow", "NUMERIC_FAULT", {            operation: safeOp, fault: "overflow", value: val        });        val = (((val % limit) + limit) % limit) & (limit - BN_1);    }    return val;}function getFormat(value) {    if (typeof (value) === "number") {        value = `fixed128x${value}`;    }    let signed = true;    let width = 128;    let decimals = 18;    if (typeof (value) === "string") {        // Parse the format string        if (value === "fixed") {            // defaults...        }        else if (value === "ufixed") {            signed = false;        }        else {            const match = value.match(/^(u?)fixed([0-9]+)x([0-9]+)$/);            assertArgument(match, "invalid fixed format", "format", value);            signed = (match[1] !== "u");            width = parseInt(match[2]);            decimals = parseInt(match[3]);        }    }    else if (value) {        // Extract the values from the object        const v = value;        const check = (key, type, defaultValue) => {            if (v[key] == null) {                return defaultValue;            }            assertArgument(typeof (v[key]) === type, "invalid fixed format (" + key + " not " + type + ")", "format." + key, v[key]);            return v[key];        };        signed = check("signed", "boolean", signed);        width = check("width", "number", width);        decimals = check("decimals", "number", decimals);    }    assertArgument((width % 8) === 0, "invalid FixedNumber width (not byte aligned)", "format.width", width);    assertArgument(decimals <= 80, "invalid FixedNumber decimals (too large)", "format.decimals", decimals);    const name = (signed ? "" : "u") + "fixed" + String(width) + "x" + String(decimals);    return { signed, width, decimals, name };}function toString(val, decimals) {    let negative = "";    if (val < BN_0) {        negative = "-";        val *= BN_N1;    }    let str = val.toString();    // No decimal point for whole values    if (decimals === 0) {        return (negative + str);    }    // Pad out to the whole component (including a whole digit)    while (str.length <= decimals) {        str = Zeros + str;    }    // Insert the decimal point    const index = str.length - decimals;    str = str.substring(0, index) + "." + str.substring(index);    // Trim the whole component (leaving at least one 0)    while (str[0] === "0" && str[1] !== ".") {        str = str.substring(1);    }    // Trim the decimal component (leaving at least one 0)    while (str[str.length - 1] === "0" && str[str.length - 2] !== ".") {        str = str.substring(0, str.length - 1);    }    return (negative + str);}/** *  A FixedNumber represents a value over its [[FixedFormat]] *  arithmetic field. * *  A FixedNumber can be used to perform math, losslessly, on *  values which have decmial places. * *  A FixedNumber has a fixed bit-width to store values in, and stores all *  values internally by multiplying the value by 10 raised to the power of *  %%decimals%%. * *  If operations are performed that cause a value to grow too high (close to *  positive infinity) or too low (close to negative infinity), the value *  is said to //overflow//. * *  For example, an 8-bit signed value, with 0 decimals may only be within *  the range ``-128`` to ``127``; so ``-128 - 1`` will overflow and become *  ``127``. Likewise, ``127 + 1`` will overflow and become ``-127``. * *  Many operation have a normal and //unsafe// variant. The normal variant *  will throw a [[NumericFaultError]] on any overflow, while the //unsafe// *  variant will silently allow overflow, corrupting its value value. * *  If operations are performed that cause a value to become too small *  (close to zero), the value loses precison and is said to //underflow//. * *  For example, an value with 1 decimal place may store a number as small *  as ``0.1``, but the value of ``0.1 / 2`` is ``0.05``, which cannot fit *  into 1 decimal place, so underflow occurs which means precision is lost *  and the value becomes ``0``. * *  Some operations have a normal and //signalling// variant. The normal *  variant will silently ignore underflow, while the //signalling// variant *  will thow a [[NumericFaultError]] on underflow. */export class FixedNumber {    /**     *  The specific fixed-point arithmetic field for this value.     */    format;    #format;    // The actual value (accounting for decimals)    #val;    // A base-10 value to multiple values by to maintain the magnitude    #tens;    /**     *  This is a property so console.log shows a human-meaningful value.     *     *  @private     */    _value;    // Use this when changing this file to get some typing info,    // but then switch to any to mask the internal type    //constructor(guard: any, value: bigint, format: _FixedFormat) {    /**     *  @private     */    constructor(guard, value, format) {        assertPrivate(guard, _guard, "FixedNumber");        this.#val = value;        this.#format = format;        const _value = toString(value, format.decimals);        defineProperties(this, { format: format.name, _value });        this.#tens = getTens(format.decimals);    }    /**     *  If true, negative values are permitted, otherwise only     *  positive values and zero are allowed.     */    get signed() { return this.#format.signed; }    /**     *  The number of bits available to store the value.     */    get width() { return this.#format.width; }    /**     *  The number of decimal places in the fixed-point arithment field.     */    get decimals() { return this.#format.decimals; }    /**     *  The value as an integer, based on the smallest unit the     *  [[decimals]] allow.     */    get value() { return this.#val; }    #checkFormat(other) {        assertArgument(this.format === other.format, "incompatible format; use fixedNumber.toFormat", "other", other);    }    #checkValue(val, safeOp) {        /*                const width = BigInt(this.width);                if (this.signed) {                    const limit = (BN_1 << (width - BN_1));                    assert(safeOp == null || (val >= -limit  && val < limit), "overflow", "NUMERIC_FAULT", {                        operation: <string>safeOp, fault: "overflow", value: val                    });                            if (val > BN_0) {                        val = fromTwos(mask(val, width), width);                    } else {                        val = -fromTwos(mask(-val, width), width);                    }                        } else {                    const masked = mask(val, width);                    assert(safeOp == null || (val >= 0 && val === masked), "overflow", "NUMERIC_FAULT", {                        operation: <string>safeOp, fault: "overflow", value: val                    });                    val = masked;                }        */        val = checkValue(val, this.#format, safeOp);        return new FixedNumber(_guard, val, this.#format);    }    #add(o, safeOp) {        this.#checkFormat(o);        return this.#checkValue(this.#val + o.#val, safeOp);    }    /**     *  Returns a new [[FixedNumber]] with the result of %%this%% added     *  to %%other%%, ignoring overflow.     */    addUnsafe(other) { return this.#add(other); }    /**     *  Returns a new [[FixedNumber]] with the result of %%this%% added     *  to %%other%%. A [[NumericFaultError]] is thrown if overflow     *  occurs.     */    add(other) { return this.#add(other, "add"); }    #sub(o, safeOp) {        this.#checkFormat(o);        return this.#checkValue(this.#val - o.#val, safeOp);    }    /**     *  Returns a new [[FixedNumber]] with the result of %%other%% subtracted     *  from %%this%%, ignoring overflow.     */    subUnsafe(other) { return this.#sub(other); }    /**     *  Returns a new [[FixedNumber]] with the result of %%other%% subtracted     *  from %%this%%. A [[NumericFaultError]] is thrown if overflow     *  occurs.     */    sub(other) { return this.#sub(other, "sub"); }    #mul(o, safeOp) {        this.#checkFormat(o);        return this.#checkValue((this.#val * o.#val) / this.#tens, safeOp);    }    /**     *  Returns a new [[FixedNumber]] with the result of %%this%% multiplied     *  by %%other%%, ignoring overflow and underflow (precision loss).     */    mulUnsafe(other) { return this.#mul(other); }    /**     *  Returns a new [[FixedNumber]] with the result of %%this%% multiplied     *  by %%other%%. A [[NumericFaultError]] is thrown if overflow     *  occurs.     */    mul(other) { return this.#mul(other, "mul"); }    /**     *  Returns a new [[FixedNumber]] with the result of %%this%% multiplied     *  by %%other%%. A [[NumericFaultError]] is thrown if overflow     *  occurs or if underflow (precision loss) occurs.     */    mulSignal(other) {        this.#checkFormat(other);        const value = this.#val * other.#val;        assert((value % this.#tens) === BN_0, "precision lost during signalling mul", "NUMERIC_FAULT", {            operation: "mulSignal", fault: "underflow", value: this        });        return this.#checkValue(value / this.#tens, "mulSignal");    }    #div(o, safeOp) {        assert(o.#val !== BN_0, "division by zero", "NUMERIC_FAULT", {            operation: "div", fault: "divide-by-zero", value: this        });        this.#checkFormat(o);        return this.#checkValue((this.#val * this.#tens) / o.#val, safeOp);    }    /**     *  Returns a new [[FixedNumber]] with the result of %%this%% divided     *  by %%other%%, ignoring underflow (precision loss). A     *  [[NumericFaultError]] is thrown if overflow occurs.     */    divUnsafe(other) { return this.#div(other); }    /**     *  Returns a new [[FixedNumber]] with the result of %%this%% divided     *  by %%other%%, ignoring underflow (precision loss). A     *  [[NumericFaultError]] is thrown if overflow occurs.     */    div(other) { return this.#div(other, "div"); }    /**     *  Returns a new [[FixedNumber]] with the result of %%this%% divided     *  by %%other%%. A [[NumericFaultError]] is thrown if underflow     *  (precision loss) occurs.     */    divSignal(other) {        assert(other.#val !== BN_0, "division by zero", "NUMERIC_FAULT", {            operation: "div", fault: "divide-by-zero", value: this        });        this.#checkFormat(other);        const value = (this.#val * this.#tens);        assert((value % other.#val) === BN_0, "precision lost during signalling div", "NUMERIC_FAULT", {            operation: "divSignal", fault: "underflow", value: this        });        return this.#checkValue(value / other.#val, "divSignal");    }    /**     *  Returns a comparison result between %%this%% and %%other%%.     *     *  This is suitable for use in sorting, where ``-1`` implies %%this%%     *  is smaller, ``1`` implies %%this%% is larger and ``0`` implies     *  both are equal.     */    cmp(other) {        let a = this.value, b = other.value;        // Coerce a and b to the same magnitude        const delta = this.decimals - other.decimals;        if (delta > 0) {            b *= getTens(delta);        }        else if (delta < 0) {            a *= getTens(-delta);        }        // Comnpare        if (a < b) {            return -1;        }        if (a > b) {            return 1;        }        return 0;    }    /**     *  Returns true if %%other%% is equal to %%this%%.     */    eq(other) { return this.cmp(other) === 0; }    /**     *  Returns true if %%other%% is less than to %%this%%.     */    lt(other) { return this.cmp(other) < 0; }    /**     *  Returns true if %%other%% is less than or equal to %%this%%.     */    lte(other) { return this.cmp(other) <= 0; }    /**     *  Returns true if %%other%% is greater than to %%this%%.     */    gt(other) { return this.cmp(other) > 0; }    /**     *  Returns true if %%other%% is greater than or equal to %%this%%.     */    gte(other) { return this.cmp(other) >= 0; }    /**     *  Returns a new [[FixedNumber]] which is the largest **integer**     *  that is less than or equal to %%this%%.     *     *  The decimal component of the result will always be ``0``.     */    floor() {        let val = this.#val;        if (this.#val < BN_0) {            val -= this.#tens - BN_1;        }        val = (this.#val / this.#tens) * this.#tens;        return this.#checkValue(val, "floor");    }    /**     *  Returns a new [[FixedNumber]] which is the smallest **integer**     *  that is greater than or equal to %%this%%.     *     *  The decimal component of the result will always be ``0``.     */    ceiling() {        let val = this.#val;        if (this.#val > BN_0) {            val += this.#tens - BN_1;        }        val = (this.#val / this.#tens) * this.#tens;        return this.#checkValue(val, "ceiling");    }    /**     *  Returns a new [[FixedNumber]] with the decimal component     *  rounded up on ties at %%decimals%% places.     */    round(decimals) {        if (decimals == null) {            decimals = 0;        }        // Not enough precision to not already be rounded        if (decimals >= this.decimals) {            return this;        }        const delta = this.decimals - decimals;        const bump = BN_5 * getTens(delta - 1);        let value = this.value + bump;        const tens = getTens(delta);        value = (value / tens) * tens;        checkValue(value, this.#format, "round");        return new FixedNumber(_guard, value, this.#format);    }    /**     *  Returns true if %%this%% is equal to ``0``.     */    isZero() { return (this.#val === BN_0); }    /**     *  Returns true if %%this%% is less than ``0``.     */    isNegative() { return (this.#val < BN_0); }    /**     *  Returns the string representation of %%this%%.     */    toString() { return this._value; }    /**     *  Returns a float approximation.     *     *  Due to IEEE 754 precission (or lack thereof), this function     *  can only return an approximation and most values will contain     *  rounding errors.     */    toUnsafeFloat() { return parseFloat(this.toString()); }    /**     *  Return a new [[FixedNumber]] with the same value but has had     *  its field set to %%format%%.     *     *  This will throw if the value cannot fit into %%format%%.     */    toFormat(format) {        return FixedNumber.fromString(this.toString(), format);    }    /**     *  Creates a new [[FixedNumber]] for %%value%% divided by     *  %%decimal%% places with %%format%%.     *     *  This will throw a [[NumericFaultError]] if %%value%% (once adjusted     *  for %%decimals%%) cannot fit in %%format%%, either due to overflow     *  or underflow (precision loss).     */    static fromValue(_value, _decimals, _format) {        const decimals = (_decimals == null) ? 0 : getNumber(_decimals);        const format = getFormat(_format);        let value = getBigInt(_value, "value");        const delta = decimals - format.decimals;        if (delta > 0) {            const tens = getTens(delta);            assert((value % tens) === BN_0, "value loses precision for format", "NUMERIC_FAULT", {                operation: "fromValue", fault: "underflow", value: _value            });            value /= tens;        }        else if (delta < 0) {            value *= getTens(-delta);        }        checkValue(value, format, "fromValue");        return new FixedNumber(_guard, value, format);    }    /**     *  Creates a new [[FixedNumber]] for %%value%% with %%format%%.     *     *  This will throw a [[NumericFaultError]] if %%value%% cannot fit     *  in %%format%%, either due to overflow or underflow (precision loss).     */    static fromString(_value, _format) {        const match = _value.match(/^(-?)([0-9]*)\.?([0-9]*)$/);        assertArgument(match && (match[2].length + match[3].length) > 0, "invalid FixedNumber string value", "value", _value);        const format = getFormat(_format);        let whole = (match[2] || "0"), decimal = (match[3] || "");        // Pad out the decimals        while (decimal.length < format.decimals) {            decimal += Zeros;        }        // Check precision is safe        assert(decimal.substring(format.decimals).match(/^0*$/), "too many decimals for format", "NUMERIC_FAULT", {            operation: "fromString", fault: "underflow", value: _value        });        // Remove extra padding        decimal = decimal.substring(0, format.decimals);        const value = BigInt(match[1] + whole + decimal);        checkValue(value, format, "fromString");        return new FixedNumber(_guard, value, format);    }    /**     *  Creates a new [[FixedNumber]] with the big-endian representation     *  %%value%% with %%format%%.     *     *  This will throw a [[NumericFaultError]] if %%value%% cannot fit     *  in %%format%% due to overflow.     */    static fromBytes(_value, _format) {        let value = toBigInt(getBytes(_value, "value"));        const format = getFormat(_format);        if (format.signed) {            value = fromTwos(value, format.width);        }        checkValue(value, format, "fromBytes");        return new FixedNumber(_guard, value, format);    }}//const f1 = FixedNumber.fromString("12.56", "fixed16x2");//const f2 = FixedNumber.fromString("0.3", "fixed16x2");//console.log(f1.divSignal(f2));//const BUMP = FixedNumber.from("0.5");//# sourceMappingURL=fixednumber.js.map
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