@def

This page tracks the current repository implementation and is written as the 0.2.0 API baseline.

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pub(all) enum Sign

enum Sign {
  Negative
  Zero
  Positive
}

• Description Represents the sign classification shared by all floating packages.

• Semantic Notes

  • Zero means "numerically zero or sign-indeterminate zero-like result" in the current package set.
  • ball_float may return Zero when the enclosure straddles both negative and positive values.

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pub(all) enum FpClass

enum FpClass {
  Finite
  Infinity
  NaN
}

• Description Shared floating-point class used by bin_float, decimal, and ball_float.

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pub(all) enum RoundingMode

enum RoundingMode {
  ToNearestEven
  TowardZero
  TowardPositive
  TowardNegative
  AwayFromZero
}

• Description Requests a rounding direction when precision reduction or approximate conversion is required.

• Semantic Notes

  • ToNearestEven is the repository default for precision-controlled constructors and conversions unless a method documents otherwise.
  • ball_float uses outward-oriented rounding choices internally when widening an enclosure.

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pub(open) trait Floating

trait Floating {
  fn classify(Self) -> FpClass
  fn sign(Self) -> Sign
  fn precision(Self) -> Int
  fn with_precision(Self, Int, RoundingMode) -> Self
  fn normalized(Self) -> Self
}

• Description The shared capability boundary for Luna Flow floating-like values.

Required Methods

• fn classify(Self) -> FpClass Returns the current classification: finite, infinity, or NaN.

• fn sign(Self) -> Sign Returns the sign classification for the current value.

• fn precision(Self) -> Int Returns the current working precision stored on the value.

• fn with_precision(Self, Int, RoundingMode) -> Self Retunes the value to a requested precision using the given rounding mode.

• fn normalized(Self) -> Self Returns the canonical normalized form for the value.

Current Implementations

• @bin_float.BinFloat
• @decimal.Decimal
• @ball_float.BallFloat

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Helper Predicates

• fn[F : Floating] is_finite(x : F) -> Bool Returns true when classify(x) == FpClass::Finite.

• fn[F : Floating] is_nan(x : F) -> Bool Returns true when classify(x) == FpClass::NaN.

• fn[F : Floating] is_infinite(x : F) -> Bool Returns true when classify(x) == FpClass::Infinity.

• fn[F : Floating] is_zero(x : F) -> Bool Returns true when x is finite and sign(x) == Sign::Zero.