Legend:
Library
Module
Module type
Parameter
Class
Class type
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]v}.
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]
The type of filter idents with (optionally multiple) qualifying package names and optional string converter. Package name None encodes the self-reference _
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 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
val unclosed_expansions : string ->((int * int) * string) list
Returns the (beginning, end) offsets and substrings of any unclosed %{ expansions
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
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.
Resolves the build, 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.