m2cli-grammar.gll

/* M2BSK -- EBNF Grammar for Modula-2 R10 Bootstrap Kernel (subset).
 *
 * Copyright (c) 2017 The Modula-2 Software Foundation
 *
 * Author & Maintainer: Benjamin Kowarsch <org.m2sf>
 *
 * @synopsis
 *
 * Modula-2 BSK is a subset of Modula-2 R10 for bootstrapping a compiler.
 *
 * This document specifies the command line argument grammar in EBNF.
 *
 * @repository
 *
 * https://github.com/m2sf/m2bsk
 *
 * @file
 *
 * m2cli-grammar.gll
 *
 * Grammar of Modula-2 command line interface.
 *
 */

grammar m2cli;

/* * *   R e s e r v e d   W o r d s   * * */

/* to do */


/* * *   N o n - T e r m i n a l   S y m b o l s   * * */

args :=
  infoRequest | compilationRequest
  ;

infoRequest :=
  --help | -h | --version | -V | --license
  ;
  
compilationRequest :=
  products? capabilities? sourceFile diagnostics?
  ;

products :=
  ( singleProduct | multipleProducts ) commentOption?
  ;

singleProduct :=
  --syntax-only | --ast-only | --graph-only | --xlat-only | --obj-only
  ;

multipleProducts :=
  ( ast | graph | xlat | obj )+
  ;

ast :=
  --ast | --no-ast
  ;

graph :=
  --graph | --no-graph
  ;

xlat :=
  --xlat | --no-xlat
  ;

obj :=
  --obj | --no-obj
  ;

commentOption :=
  --preserve-comments | --strip-comments
  ;

capabilities :=
/* this should be simplified to a simple switch --foreign-identifiers */
  ( dollarIdentifiers | lowlineIdentifiers )+
  ;

sourceFile :=
  <platform dependent path/filename>
  ;

diagnostics :=
  ( --verbose | -v | --lexer-debug | --parser-debug | --print-settings |
    --errant-semicolons )+
  ;


/* * *   T e r m i n a l   S y m b o l s   * * */


QuotedLiteral :=
  SingleQuotedString | DoubleQuotedString
  ;

.SingleQuotedString :=
  "'" ( QuotableCharacter | '"' )* "'"
  ;

.DoubleQuotedString :=
  '"' ( QuotableCharacter | "'" )* '"'
  ;

.QuotableCharacter :=
  Digit | Letter | Space | NonAlphanumQuotable
  ;
  
.Digit := '0' .. '9' ;

.Letter := 'a' .. 'z' | 'A' .. 'Z' ;

.Space := 0u20 ;

.NonAlphaNumQuotable :=
  '!' | '#' | '$' | '%' | '&' | '(' | ')' | '*' | '+' | ',' |
  '-' | '.' | '/' | ':' | ';' | '<' | '=' | '>' | '?' | '@' |
  '[' | '\' | ']' | '^' | '_' | '`' | '{' | '|' | '}' | '~'
  ;

endg m2cli.