OpamFilter
Formulas on variables, as used in opam files build scripts
Filters are a small language of formulas over strings and booleans used for conditions and text replacements. It has relational operators over strings (using version-number comparison), And, Or and Not boolean operations, dynamic casting (using strings "true" and "false"), and string interpolation. Variables are resolved using a user function returning an option, undefined values are propagated.
String interpolation uses the syntax %{identifier}%
Identifiers have the form
[package:]var[?str_if_true:str_if_false_or_undef]
The last optional part specifies a conversion from boolean to static strings.
The syntax pkg1+pkg2+pkgn:var
is allowed as a shortcut to pkg1:var & pkg2:var & pkgn:var
.
The special variable pkg:enable
is allowed as a shortcut for pkg:installed?enable:disable
val to_string : OpamTypes.filter -> string
Pretty-print
val fold_down_left : ('a -> OpamTypes.filter -> 'a) -> 'a -> OpamTypes.filter -> 'a
Folds on the tree of a filter
val map_up : (OpamTypes.filter -> OpamTypes.filter) -> OpamTypes.filter -> OpamTypes.filter
Maps on all nodes of a filter, bottom-up
val variables : OpamTypes.filter -> OpamTypes.full_variable list
Returns all the variables appearing in a filter (including the ones within string interpolations
type env = OpamTypes.full_variable -> OpamTypes.variable_contents option
Type of filter environment.
type fident = OpamTypes.name option list * OpamTypes.variable * (string * string) option
The type of filter idents with (optionally multiple) qualifying package names and optional string converter. Package name None
encodes the self-reference _
val map_variables : (OpamTypes.full_variable -> OpamTypes.full_variable) -> OpamTypes.filter -> OpamTypes.filter
Maps on all variables appearing in a filter. The case where package variables are renamed differently and appear in a filter ident of the form %{pkg1+pkg2:var}%
is not supported and raises Invalid_argument
.
val map_variables_in_string : (OpamTypes.full_variable -> OpamTypes.full_variable) -> string -> string
Same limitation as map_variables
val map_variables_in_fident : (OpamTypes.full_variable -> OpamTypes.full_variable) -> fident -> fident
Does not handle rewriting the variables to different names (which can't be expressed with a fident
anymore), and raises Invalid_argument
val distribute_negations : ?neg:bool -> OpamTypes.filter -> OpamTypes.filter
Distributes the negations to apply only to atoms
val expand_string : ?partial:bool -> ?default:(string -> string) ->
env -> string -> string
Rewrites string interpolations within a string. default
is applied to the fident string (e.g. what's between %{
and }%
) when the expansion is undefined. If unspecified, this raises Failure
.
With partial
, default
defaults to the identity, and is otherwise expected to return a fident. In this case, the returned string is supposed to be expanded again (expansion results are escaped, escapes are otherwise kept). This makes the function idempotent
Returns the (beginning, end) offsets and substrings of any unclosed %{
expansions
val eval : ?default:OpamTypes.variable_contents -> env -> OpamTypes.filter -> OpamTypes.variable_contents
Computes the value of a filter. May raise Failure
if default
isn't provided
val eval_to_bool : ?default:bool -> env -> OpamTypes.filter -> bool
Like eval
but casts the result to a bool. Raises Invalid_argument
if not a valid bool and no default supplied.
val opt_eval_to_bool : env -> OpamTypes.filter option -> bool
Same as eval_to_bool
, but takes an option as filter and returns always true
on None
, false
when the filter is Undefined
. This is the most common behaviour for using "filters" for filtering
val eval_to_string : ?default:string -> env -> OpamTypes.filter -> string
Like eval
but casts the result to a string
val partial_eval : env -> OpamTypes.filter -> OpamTypes.filter
Reduces what can be, keeps the rest unchanged
val ident_of_var : OpamTypes.full_variable -> fident
Wraps a full_variable into a fident accessor
val ident_of_string : string -> fident
A fident accessor directly referring a variable with the given name
val ident_value : ?default:OpamTypes.variable_contents -> env -> fident -> OpamTypes.variable_contents
Resolves a filter ident. Like eval
, may raise Failure if no default is provided
Like ident_value
, but casts the result to a string
Like ident_value
, but casts the result to a bool
val expand_interpolations_in_file : env -> OpamTypes.basename -> unit
Rewrites basename
.in to basename
, expanding interpolations. If the first line begins "opam-version:"
, assumes that expansion of variables within strings should be properly escaped. In particular, this means that Windows paths should expand correctly when generating .config files.
val commands : env -> OpamTypes.command list -> string list list
Processes filters evaluation in a command list: parameter expansion and conditional filtering
val single_command : env -> OpamTypes.arg list -> string list
Process a simpler command, without filters
val commands_variables : OpamTypes.command list -> OpamTypes.full_variable list
Extracts variables appearing in a list of commands
val of_formula : ('a -> OpamTypes.filter) -> 'a OpamTypes.generic_formula -> OpamTypes.filter
Converts a generic formula to a filter, given a converter for atoms
val filter_formula : ?default_version:OpamTypes.version -> ?default:bool -> env -> OpamTypes.filtered_formula -> OpamTypes.formula
Resolves the filter in a filtered formula, reducing to a pure formula.
default
is the assumed result for undefined filters. If a version filter doesn't resolve to a valid version, the constraint is dropped unless default_version
is specified.
May raise, as other filter functions, if default
is not provided and filters don't resolve.
val partial_filter_formula : env -> OpamTypes.filtered_formula -> OpamTypes.filtered_formula
Reduces according to what is defined in env
, and returns the simplified formula
val gen_filter_formula : ('a -> [< `True | `False | `Formula of 'b OpamTypes.generic_formula ]) -> ('c * 'a) OpamFormula.formula -> ('c * 'b OpamTypes.generic_formula) OpamFormula.formula
A more generic formula reduction function, that takes a "partial resolver" as argument
val string_of_filtered_formula : OpamTypes.filtered_formula -> string
val variables_of_filtered_formula : OpamTypes.filtered_formula -> OpamTypes.full_variable list
val filter_deps : build:bool -> post:bool -> ?test:bool -> ?doc:bool -> ?dev:bool ->
?default_version:OpamTypes.version -> ?default:bool -> OpamTypes.filtered_formula -> OpamTypes.formula
Resolves the build, post, test, doc, dev flags in a filtered formula (which is supposed to have been pre-processed to remove switch and global variables). default
determines the behaviour on undefined filters, and the function may raise if it is undefined. If a constraint resolves to an invalid version, it is dropped, or replaced with default_version
if specified. If test, doc or dev are unspecified, they are assumed to be filtered out already and encountering them will raise an assert.
val deps_var_env : build:bool -> post:bool -> ?test:bool -> ?doc:bool -> ?dev:bool -> env
The environment used in resolving the dependency filters, as per filter_deps
.
val simplify_extended_version_formula : OpamTypes.filter OpamTypes.filter_or_constraint OpamFormula.formula -> OpamTypes.filter OpamTypes.filter_or_constraint OpamFormula.formula option
Like OpamFormula.simplify_version_formula
, but on filtered formulas (filters are kept unchanged, but put in front)
val atomise_extended : OpamTypes.filtered_formula -> (OpamPackage.Name.t * (OpamTypes.filter * (OpamTypes.relop * OpamTypes.filter) option)) OpamFormula.formula
val sort_filtered_formula : ((OpamTypes.name * OpamTypes.filter OpamTypes.filter_or_constraint OpamFormula.formula) -> (OpamTypes.name * OpamTypes.filter OpamTypes.filter_or_constraint OpamFormula.formula) -> int) -> OpamTypes.filtered_formula -> OpamTypes.filtered_formula