Probably 4.0.0

Probably 4.0.0 includes changes from Prodigy, which will be presented at CAV 2022. Thanks to all contributors, especially @Legotier for working on this merge (PR #3).

This release contains a number of breaking changes.

Breaking Changes

• Probably now requires Python 3.9.
• Renamed Binop.LE to Binop.LT.
• The multiplication operator * now has the same precedence as /. This means that : now binds less strongly than *.
• Renamed FloatLitExpr to RealLitExpr and FloatType to RealType.
• Renamed UniformExpr to DUniformExpr.
• Renamed Assoc.Left/Assoc.Right to Assoc.LEFT/Assoc.RIGHT.
• Compared to prodigy's implementation, the type checker now allows non-constant expressions as distribution expression parameters.

Added

• Added parameters: These can be used and declared like variables, but cannot be assigned to. See ParameterDecl.
• Added new binops: GT, GEQ, POWER, and MODULO.
• New support for variables of RealType.
• Added ObserveInstr.
• Added OptimizationQuery.
• Added ProbabilityQueryInstr.
• Added PrintInstr.
• Added PlotInstr.
• Added LoopInstr.
• Added ExpectationInstr.
• Added more distribution expressions: CUniformExpr, GeometricExpr, BernoulliExpr, PoissonExpr, LogDistExpr, BinomialExpr, IidSampleExpr and DistrExpr.

Fixed

• TickInstr are now type-checked.

Known Issues

• We currently rely on undocumented behavior of an old version of networkx. See #3 (comment)