Difference between revisions of "Syntax checking/Parser"

(added eiffel.y)
(suggestion for implementation)
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====EIFFEL_CLASS_C====
 
====EIFFEL_CLASS_C====
 
* features build_ast and parse_ast show how the parser can be used.
 
* features build_ast and parse_ast show how the parser can be used.
 +
 +
 +
==Implementation==
 +
* based on Paul's code
 +
===ERROR classes===
 +
* Create new SYNTAX_ERROR classes that correspond to Paul's classes, but fit into the current hierarchy
 +
* store start and end position of the error
 +
===extend parser to generate the right ERRORs===
 +
* Integrate Paul's changes to eiffel.l and eiffel.y into the current versions.
 +
* add facilities from Paul's EIFFEL_PARSER_ERROR_REPORTER
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** in existing class like EIFFEL_PARSER_SKELETON (EP_ERROR_REPORTER only inherits SHARED_ERROR_HANDLER and so does EP_SKELETON
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** in new class

Revision as of 06:34, 19 May 2006

back to Syntax checking page

Important Classes/Files

eiffel.y

  • Eiffel grammar description.
  • use geyacc to generate eiffel_parser.e from this file

EIFFEL_PARSER

  • inherits from EIFFEL_PARSER_SKELETON (where the features parse, parse_string, make_with_factory are implemented)
  • make_with_factory (a_factory: AST_FACTORY): give argument of type AST_NULL_FACTORY (inherits from AST_FACTORY)
  • parse (a_file: KL_BINARY_INPUT_FILE) and parse_from_string (a_string: STRING): Both save the results in match_list: LEAF_AS_LIST.

CLASS_AS

  • AST of a class

ERROR

  • deferred; superclass of all error types like EIFFEL_ERROR or SYNTAX_ERROR
  • features line, column: INTEGER give location of error

ERROR_HANDLER

  • feature error_list: ERROR is a list of errors found by the parser

SHARED_ERROR_HANDLER

  • singleton used by all relevant classes

EIFFEL_CLASS_C

  • features build_ast and parse_ast show how the parser can be used.


Implementation

  • based on Paul's code

ERROR classes

  • Create new SYNTAX_ERROR classes that correspond to Paul's classes, but fit into the current hierarchy
  • store start and end position of the error

extend parser to generate the right ERRORs

  • Integrate Paul's changes to eiffel.l and eiffel.y into the current versions.
  • add facilities from Paul's EIFFEL_PARSER_ERROR_REPORTER
    • in existing class like EIFFEL_PARSER_SKELETON (EP_ERROR_REPORTER only inherits SHARED_ERROR_HANDLER and so does EP_SKELETON
    • in new class