A Version represents the version of a software entity.

Instances of Eq and Ord are provided, which gives exact equality and lexicographic ordering of the version number components (i.e. 2.1 > 2.0, 1.2.3 > 1.2.2, etc.).

This type is opaque and distinct from the Version type in Data.Version since Cabal-2.0. The difference extends to the Binary instance using a different (and more compact) encoding.

Since: Cabal-syntax-2.0.0.2

Version intervals with exclusive or inclusive bounds, in all combinations:

1. \( (lb,ub) \) meaning \( lb < \_ < ub \).
2. \( (lb,ub] \) meaning \( lb < \_ ≤ ub \).
3. \( [lb,ub) \) meaning \( lb ≤ \_ < ub \).
4. \( [lb,ub] \) meaning \( lb ≤ \_ < ub \).

The upper bound can also be missing, meaning "\( ..,∞) \)".

The version range == v.

withinRange v' (thisVersion v) = v' == v

The version range vr1 || vr2.

  withinRange v' (unionVersionRanges vr1 vr2)
= withinRange v' vr1 || withinRange v' vr2

Simplify a VersionRange expression. For non-empty version ranges this produces a canonical form. Empty or inconsistent version ranges are left as-is because that provides more information.

If you need a canonical form use fromVersionIntervals . toVersionIntervals

It satisfies the following properties:

withinRange v (simplifyVersionRange r) = withinRange v r

    withinRange v r = withinRange v r'
==> simplifyVersionRange r = simplifyVersionRange r'
 || isNoVersion r
 || isNoVersion r'

Convert a VersionIntervals value back into a VersionRange expression representing the version intervals.

View a VersionRange as a sequence of separated intervals.

This provides a canonical view of the semantics of a VersionRange as opposed to the syntax of the expression used to define it. For the syntactic view use foldVersionRange.

Canonical means that two semantically equal ranges translate to the same [VersionInterval], thus its Eq instance can decide semantical equality of ranges.

In the returned sequence, each interval is non-empty. The sequence is in increasing order and the intervals are separated, i.e., they neither overlap nor touch. Therefore only the first and last interval can be unbounded. The sequence can be empty if the range is empty (e.g. a range expression like > 2 && < 1).

Other checks are trivial to implement using this view. For example:

isNoVersion vr | [] <- asVersionIntervals vr = True
               | otherwise                   = False

isSpecificVersion vr
   | [(LowerBound v  InclusiveBound
      ,UpperBound v' InclusiveBound)] <- asVersionIntervals vr
   , v == v'   = Just v
   | otherwise = Nothing

A Version type by Data.Version.

Parse a version text. There must not be any trailing characters after a valid version text.