| // Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| part of dart.core; |
| |
| // TODO: Convert this abstract class into a concrete class double |
| // that uses the patch class functionality to account for the |
| // different platform implementations. |
| |
| /** |
| * A double-precision floating point number. |
| * |
| * Representation of Dart doubles containing double specific constants |
| * and operations and specializations of operations inherited from |
| * [num]. Dart doubles are 64-bit floating-point numbers as specified in the |
| * IEEE 754 standard. |
| * |
| * The [double] type is contagious. Operations on [double]s return |
| * [double] results. |
| * |
| * It is a compile-time error for a class to attempt to extend or implement |
| * double. |
| */ |
| abstract class double extends num { |
| static const double NAN = 0.0 / 0.0; |
| static const double INFINITY = 1.0 / 0.0; |
| static const double NEGATIVE_INFINITY = -INFINITY; |
| static const double MIN_POSITIVE = 5e-324; |
| static const double MAX_FINITE = 1.7976931348623157e+308; |
| |
| double remainder(num other); |
| |
| /** Addition operator. */ |
| double operator +(num other); |
| |
| /** Subtraction operator. */ |
| double operator -(num other); |
| |
| /** Multiplication operator. */ |
| double operator *(num other); |
| |
| double operator %(num other); |
| |
| /** Division operator. */ |
| double operator /(num other); |
| |
| /** |
| * Truncating division operator. |
| * |
| * The result of the truncating division `a ~/ b` is equivalent to |
| * `(a / b).truncate()`. |
| */ |
| int operator ~/(num other); |
| |
| /** Negate operator. */ |
| double operator -(); |
| |
| /** Returns the absolute value of this [double]. */ |
| double abs(); |
| |
| /** |
| * Returns the sign of the double's numerical value. |
| * |
| * Returns -1.0 if the value is less than zero, |
| * +1.0 if the value is greater than zero, |
| * and the value itself if it is -0.0, 0.0 or NaN. |
| */ |
| double get sign; |
| |
| /** |
| * Returns the integer closest to `this`. |
| * |
| * Rounds away from zero when there is no closest integer: |
| * `(3.5).round() == 4` and `(-3.5).round() == -4`. |
| * |
| * If `this` is not finite (`NaN` or infinity), throws an [UnsupportedError]. |
| */ |
| int round(); |
| |
| /** |
| * Returns the greatest integer no greater than `this`. |
| * |
| * If `this` is not finite (`NaN` or infinity), throws an [UnsupportedError]. |
| */ |
| int floor(); |
| |
| /** |
| * Returns the least integer no smaller than `this`. |
| * |
| * If `this` is not finite (`NaN` or infinity), throws an [UnsupportedError]. |
| */ |
| int ceil(); |
| |
| /** |
| * Returns the integer obtained by discarding any fractional |
| * digits from `this`. |
| * |
| * If `this` is not finite (`NaN` or infinity), throws an [UnsupportedError]. |
| */ |
| int truncate(); |
| |
| /** |
| * Returns the integer double value closest to `this`. |
| * |
| * Rounds away from zero when there is no closest integer: |
| * `(3.5).roundToDouble() == 4` and `(-3.5).roundToDouble() == -4`. |
| * |
| * If this is already an integer valued double, including `-0.0`, or it is not |
| * a finite value, the value is returned unmodified. |
| * |
| * For the purpose of rounding, `-0.0` is considered to be below `0.0`, |
| * and `-0.0` is therefore considered closer to negative numbers than `0.0`. |
| * This means that for a value, `d` in the range `-0.5 < d < 0.0`, |
| * the result is `-0.0`. |
| */ |
| double roundToDouble(); |
| |
| /** |
| * Returns the greatest integer double value no greater than `this`. |
| * |
| * If this is already an integer valued double, including `-0.0`, or it is not |
| * a finite value, the value is returned unmodified. |
| * |
| * For the purpose of rounding, `-0.0` is considered to be below `0.0`. |
| * A number `d` in the range `0.0 < d < 1.0` will return `0.0`. |
| */ |
| double floorToDouble(); |
| |
| /** |
| * Returns the least integer double value no smaller than `this`. |
| * |
| * If this is already an integer valued double, including `-0.0`, or it is not |
| * a finite value, the value is returned unmodified. |
| * |
| * For the purpose of rounding, `-0.0` is considered to be below `0.0`. |
| * A number `d` in the range `-1.0 < d < 0.0` will return `-0.0`. |
| */ |
| double ceilToDouble(); |
| |
| /** |
| * Returns the integer double value obtained by discarding any fractional |
| * digits from `this`. |
| * |
| * If this is already an integer valued double, including `-0.0`, or it is not |
| * a finite value, the value is returned unmodified. |
| * |
| * For the purpose of rounding, `-0.0` is considered to be below `0.0`. |
| * A number `d` in the range `-1.0 < d < 0.0` will return `-0.0`, and |
| * in the range `0.0 < d < 1.0` it will return 0.0. |
| */ |
| double truncateToDouble(); |
| |
| /** |
| * Provide a representation of this [double] value. |
| * |
| * The representation is a number literal such that the closest double value |
| * to the representation's mathematical value is this [double]. |
| * |
| * Returns "NaN" for the Not-a-Number value. |
| * Returns "Infinity" and "-Infinity" for positive and negative Infinity. |
| * Returns "-0.0" for negative zero. |
| * |
| * For all doubles, `d`, converting to a string and parsing the string back |
| * gives the same value again: `d == double.parse(d.toString())` (except when |
| * `d` is NaN). |
| */ |
| String toString(); |
| |
| /** |
| * Parse [source] as an double literal and return its value. |
| * |
| * Accepts an optional sign (`+` or `-`) followed by either the characters |
| * "Infinity", the characters "NaN" or a floating-point representation. |
| * A floating-point representation is composed of a mantissa and an optional |
| * exponent part. The mantissa is either a decimal point (`.`) followed by a |
| * sequence of (decimal) digits, or a sequence of digits |
| * optionally followed by a decimal point and optionally more digits. The |
| * (optional) exponent part consists of the character "e" or "E", an optional |
| * sign, and one or more digits. |
| * |
| * Leading and trailing whitespace is ignored. |
| * |
| * If the [source] is not a valid double literal, the [onError] |
| * is called with the [source] as argument, and its return value is |
| * used instead. If no `onError` is provided, a [FormatException] |
| * is thrown instead. |
| * |
| * The [onError] function is only invoked if [source] is a [String] with an |
| * invalid format. It is not invoked if the [source] is invalid for some |
| * other reason, for example by being `null`. |
| * |
| * Examples of accepted strings: |
| * |
| * "3.14" |
| * " 3.14 \xA0" |
| * "0." |
| * ".0" |
| * "-1.e3" |
| * "1234E+7" |
| * "+.12e-9" |
| * "-NaN" |
| */ |
| external static double parse(String source, |
| [double onError(String source)]); |
| } |