4.0.0

CHANGES:

• LSP:
  • New: language server elpi-lsp supporting type information via hovering,
    jump to definition and semantic highlighting. See lsp/README.md
  • New: elpi-webrunner npm package containing the lsp server that runs in a
    web worker, compiled to WebAssembly and to JavaScript. Moreover
    part of the API modules Setup, Parse, Compile and Execute
    exposed JavaScript. See webrunner/README.md
• Compiler:
  • Change: new field max_errors of Compile.flags
  • Change: the passes can be error resilient: they return their result and
    the list of the errors found. With Compile.flags.max_errors = 0 they do
    stop at the first error, as before.
    See also the flag -max-errors N to elpi.
  • Change: an undeclared global is reported by a warning of its own, located
    at its first occurrence (formerly one warning, without a location, for
    all the undeclared globals).
• API:
  • New: module LSP, with what the language server needs
  • Change: API.Compile.hover is now API.LSP.hover
  • Change: new module Error: the type of errors Error.t (component,
    location, message), printers, the exception Error.ElpiError (formerly
    Compile.CompileError).
  • Change: Setup.set_error, set_anomaly, set_type_error and
    Utils.error, anomaly, type_error are removed; the errors of the
    builtins can be redirected with Builtin.set_runtime_error,
    set_runtime_anomaly, set_runtime_type_error (they take a
    Builtin.runtime_error_hook, a function that raises).
  • Change: the parser and the passes
    of the compiler return their warnings (Error.warning) with their result
    and their errors; Setup.set_warn is removed. The warnings at run time
    (Builtin.warn, formerly Utils.warn) can be redirected with
    Builtin.set_runtime_warn.
    Setup.warning_id is now Error.warning_id.
  • Change: Parse.goal and Parse.goal_from are now Parse.query and
    Parse.query_from; like Compile.query, they return the query or its
    syntax error (instead of raising Parse.ParseError), and its warnings.
• Parser:
  • Change: Parse.program and Parse.program_from are error
    resilient when max_errors > 0: a declaration with a syntax error is
    skipped up to the next . and dropped, and they return the program and the
    list of the errors like the passes of the compiler.
  • Change: a syntax error in an accumulated file is located on the
    accumulate directive, its message gives the position in the file.
  • New: the comment block on the line before a declaration (pred, func,
    type, kind...) is its documentation and is used by the LSP server.
• Builtins:
  • New: reset_new_int N: resets the counter of new_int to N, so the
    next new_int gives N + 1 (its values are increasing only between two
    resets)