# Module OpamFormula

    module OpamFormula: sig .. end

Management of formulas

    type relop = [ `Eq | `Geq | `Gt | `Leq | `Lt | `Neq ]

binary operations (compatible with the Dose type for Cudf operators !)

    val string_of_relop : relop -> string

Pretty-printing of relops

    val relop_of_string : string -> relop

Parsing relops

    type version_constraint = relop * OpamPackage.Version.t

Version constraints for OPAM

    type atom = OpamPackage.Name.t * version_constraint option

Formula atoms for OPAM

    val string_of_atom : atom -> string

Pretty-printing of atoms

    val short_string_of_atom : atom -> string

The compact atom format used in requests, "pkgOPvers", with '.' allowed instead of '='

    val string_of_atoms : atom list -> string

Prints atoms as a conjunction ("&") using the short format

    val check : atom -> OpamPackage.t -> bool

Checks if a package verifies an atom

    type 'a conjunction = 'a list

AND formulas

    val string_of_conjunction : ('a -> string) -> 'a conjunction -> string

Pretty print AND formulas

    type 'a disjunction = 'a list

OR formulas

    val string_of_disjunction : ('a -> string) -> 'a disjunction -> string

Pretty print OR formulas

    type 'a cnf = 'a disjunction conjunction

CNF formulas (Conjunctive Normal Form)

    type 'a dnf = 'a conjunction disjunction

DNF formulas (Disjunctive Normal Form)

    val string_of_cnf : ('a -> string) -> 'a cnf -> string

Pretty print CNF formulas

    val string_of_dnf : ('a -> string) -> 'a dnf -> string

Pretty print DNF formulas

    type 'a formula =

`|` | `Empty`
`|` | `Atom of `'a``
`|` | `Block of `'a formula``
`|` | `And of `'a formula * 'a formula``
`|` | `Or of `'a formula * 'a formula``

General formulas

    val eval : ('a -> bool) -> 'a formula -> bool

Eval a formula

    val check_relop : relop -> int -> bool

Check a relational operator against an integer from compare

    val eval_relop : relop -> OpamPackage.Version.t -> OpamPackage.Version.t -> bool

Evaluate a relational operator between versions

    val neg_relop : relop -> relop

    val string_of_formula : ('a -> string) -> 'a formula -> string

Pretty print a formula

    val ands : 'a formula list -> 'a formula

Convert a list of formulas to an AND-formula (`Empty` formulas are ignored)

    val ands_to_list : 'a formula -> 'a formula list

Converts back an AND-formula to a list (flattens top-level ands)

    val ors : 'a formula list -> 'a formula

Convert a list of formulas to an OR-formula (`Empty` formulas are ignored)

    val ors_to_list : 'a formula -> 'a formula list

Converts back an OR-formula to a list (flattens top-level ors)

    val map : ('a -> 'b formula) ->
           'a formula -> 'b formula

Map on atoms. Atoms for which the given function returns Empty will be simply removed

    val map_formula : ('a formula -> 'a formula) ->
           'a formula -> 'a formula

Maps top-down on a formula

    val neg : ('a -> 'a) -> 'a formula -> 'a formula

Negates a formula (given the function to negate atoms)

    val iter : ('a -> unit) -> 'a formula -> unit

Iter function

    val fold_left : ('a -> 'b -> 'a) -> 'a -> 'b formula -> 'a

Fold function

    type version_formula = version_constraint formula

Expressions composed entirely of version constraints

    type t = (OpamPackage.Name.t * version_formula) formula

An atom is: `name` * (`relop` * `version`) formula. Examples of valid formulae:

- "foo" {> "1" & (<"3" | ="5")}
- "foo" {= "1" | > "4"} | ("bar" "bouh")

    val cnf_of_formula : 'a formula -> 'a formula

Convert a formula to CNF

    val dnf_of_formula : 'a formula -> 'a formula

Convert a formula to DNF

    val to_atom_formula : t -> atom formula

Transform a formula where versions can be expressed using formulas to a flat atom formula

    val of_atom_formula : atom formula -> t

Convert an atom-formula to a t-formula

    val simplify_version_formula : version_formula -> version_formula

Reduces the formula, finding a shorter description of the same version set. Keeps conflicting formula, for documentation, when the set is empty.

## Atoms

    val atoms : t -> atom list

Return all the atoms

    val to_string : t -> string

Pretty print the formula

    val to_conjunction : t -> atom conjunction

Return a conjunction. If the initial formula is not a conjunction, then fail.

    val of_conjunction : atom conjunction -> t

Return a formula from a conjunction of atoms

    val to_disjunction : t -> atom disjunction

Return a disjunction. It the initial formula is not a disjunction, then fail.

    val of_disjunction : atom disjunction -> t

Return a formula from a disjunction of atoms

    val to_cnf : t -> atom cnf

Return an equivalent CNF formula

    val to_dnf : t -> atom dnf

Return an equivalent DNF formula

    type 'a ext_package_formula = (OpamPackage.Name.t * ('a * version_formula)) formula

Formula over versionned packages with additional flags (used to handle eg. build-deps)

    val formula_of_extended : filter:('a -> bool) -> 'a ext_package_formula -> t

Turns an extended package formula to a normal formula, by filtering out the packages on the flags of which `filter` returns `false`.