package cudf

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Parser for CUDF related documents

type cudf_parser

a CUDF parser opened on some input source

exception Parse_error of string * Cudf_types.loc

Error during parsing (syntax error, type error, ...). Arguments are error message and error location.

val from_in_channel : ?typedecl:Cudf_conf.stanza_typedecl -> in_channel -> cudf_parser

create a CUDF parser reading data from an input channel

  • parameter typedecl

    (initial) per-stanza and per-property type declarations to be used while parsing. Default: Cudf_conf.stanza_typedecl

val from_IO_in_channel : ?typedecl:Cudf_conf.stanza_typedecl -> IO.input -> cudf_parser

create a CUDF parser reading data from an Extlib input channel

  • parameter typedecl

    (initial) per-stanza and per-property type declarations to be used while parsing. Default: Cudf_conf.stanza_typedecl

val from_file : ?typedecl:Cudf_conf.stanza_typedecl -> string -> cudf_parser

create a CUDF parser reading data from a file

val close : cudf_parser -> unit

Dispose a CUDF parser.

Afterwards, the parser should not be used any longer

Full CUDF document parsing

"parse_*" functions offer plain syntax parsing, with no semantic interpretation of what is being parsed. "load_*" functions offer the latter, hence also checking for semantic constraints (such as the lack of key duplication).

All full parsing function are granted to raise only Cudf_parser.Parse_error; finer grained exception are mapped to it.

val parse : cudf_parser -> Cudf.preamble option * Cudf.package list * Cudf.request option

parse a CUDF document (or a universe) as a whole

  • returns

    a triple preamble, packages, request where preamble and request are returned only if actually met in the parsed document. Note that a document with no request part is not a valid CUDF document (but might still be used to represent solver solutions, for instance).

  • raises Parse_error

    when an error during parsing is encountered (might be a syntax error, a type error, ..)

val load : cudf_parser -> Cudf.preamble option * Cudf.universe * Cudf.request option

same as Cudf_parser.parse, but additionally loads the package list as an abstract Cudf.universe.

Note: to load compact universes (i.e. only containing package names, versions, and installed status) that will be tested as solutions you should use Cudf_parser.load_solution instead: the present function does not expand missing metadata with respect to the initial status.

val load_solution : cudf_parser -> Cudf.universe -> Cudf.preamble option * Cudf.universe

Load a solution wrt to a given CUDF document, whose universe is given.

Solution format is as per Appendix B of CUDF 2.0 spec

val parse_from_file : ?typedecl:Cudf_conf.stanza_typedecl -> string -> Cudf.preamble option * Cudf.package list * Cudf.request option

Shorthand: parse a file given its name

val load_from_file : ?typedecl:Cudf_conf.stanza_typedecl -> string -> Cudf.preamble option * Cudf.universe * Cudf.request option

Shorthand: load from a file given its name

val load_solution_from_file : string -> Cudf.universe -> Cudf.preamble option * Cudf.universe

Shorthand: load a solution from a file given its name

Item-by-item CUDF parsing
val parse_item : cudf_parser -> Cudf.cudf_item

Parse the next information item (either a package description, a user request, or a preamble) from the given input channel.

Beware that parsing is stateful; in particular when the preamble is parsed, the list of allowed properties for future package stanzas is internally updated.

Low-level parsing functions

The following parsing function usually raise fine grained exceptions such as Cudf_types.Syntax_error and Cudf_types.Type_error.

type loc_map = (string * Cudf_types.loc) list
val parse_stanza : cudf_parser -> loc_map * string Cudf_types.stanza

Parse a file stanza (i.e., a RFC822-like stanza, with the notable simplification that all field/value pairs are one-liners). Strip any heading blanks lines leading to the first available field/value pair.

  • returns

    an associative list mapping field name to field values and a location map mapping field names to locations

  • raises End_of_file

    if no other stanza is available due to reached EOF

Type check an untyped stanza according to a given set of type declarations. Also take care of default values, adding missing properties where needed; fail if a required property is missing.

  • parameter loc

    location map from prop name to locations, default is None (i.e. use dummy locations)

  • raises Syntax_error

    if a property does not match its declared type; this exception is also raised when an undeclared property is encountered

  • raises Type_error

    when a property has a value of the wrong type