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/* This test file tests Kate's ANTLR highlighting
compilable bt ANTLR although not directly:
grammar can be alone file for both parser and lexer
or two files
This file is merged TestParser.g4 and TestLexer.g4
this lines also tests regions of multiline comment
*/
//file TestParser.g4
parser grammar TestParser;
options { tokenVocab = TestLexer; }
// The main entry point for parsing a grammar.
startRule
: (expression | STRING)+ EOF
;
expression
: expression PLUS mulExpr
| expression MINUS mulExpr
| mulExpr
;
mulExpr
: mulExpr MUL unaryExpr
| mulExpr DIV unaryExpr
| unaryExpr
;
unaryExpr
: atom
| LPAR expression RPAR
;
atom
: IDENT
| number
;
number
: INT
| FLOAT
;
//================================
//file TestLexer.g4
lexer grammar TestLexer;
/*'channels' and '{' must be in one line
to correct highlighting, highlighter can't
recognize regular expression "(options|tokens|channels)(?=([\s]*{))"
where apart from \s whitrspaces are end of lines
*/
channels { OFF_CHANNEL , COMMENT }
PLUS
: '+'
;
MINUS
: '-'
;
MUL
: '*'
;
DIV
: '/'
;
LPAR
: '('
;
RPAR
: ')'
;
IDENT
: Nondigit
( Nondigit
| Digit
)*
;
fragment
Digit
: [0-9]
;
fragment
NonzeroDigit
: [1-9]
;
fragment
Nondigit
: [a-zA-Z_]
;
Sign
: '+' | '-'
;
INT
: Sign? (NonzeroDigit Digit* | '0')
;
fragment
DigitSequence
: Digit+
;
fragment
ExponentPart
: [eE] Sign? DigitSequence
;
fragment
FractionalConstant
: DigitSequence? '.' DigitSequence
| DigitSequence '.'
;
FLOAT
: (FractionalConstant ExponentPart? | DigitSequence ExponentPart)
;
fragment
EscapeSequence
: '\\' ['"?abfnrtvhe\\]
;
//between [] is charset , test escape \
fragment
SChar
: ~["\\\r\n]
| EscapeSequence
;
STRING
: '"' SChar* '"'
;
|
