# grammar grammar

## terminals

ANY =| !'' ;

SPACE       =| ' ';
TAB         =| '\t';
RETURN      =| '\r';
NEWLINE     =| '\n';
SEMICOLON   =| ';';
HASH        =| '#';
EQUAL       =| '=';
PIPE        =| '|';
EXCLAMATION =| '!';
QUESTION    =| '?';
PLUS        =| '+';
STAR        =| '*';
APOSTROPHE  =| '\'';
BACKSLASH   =| '\\';
DOT         =| '.';

## rules

start =| _. rule* ;

_ =| whitespace* ;

whitespace =
| ' \t\r\n'
| comment.
;

comment =| HASH. commented* NEWLINE. ;

commented =| !'\n' ;

rule =| id. EQUAL. option* SEMICOLON. ;

id =| alpha. alphanum* ;

alpha =
| '_'
| 'abcdefghijklmnopqrstuvwxyz'
| 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
;

alphanum =
| alpha.
| numeric.
;

numeric =| '0123456789' ;

option =| PIPE. expr* ;

expr = # XXX
#| id # the sequential issue is here
| id. DOT. # add suffix, resolve sequential issue
| id. QUESTION.
| id. PLUS.
| id. STAR.
| term.
| byte.
;

term =| EXCLAMATION? APOSTROPHE. escaped* APOSTROPHE. ;

escaped =
# not BACKSLASH, not APOSTROPHE
| !'\\\''
| BACKSLASH. !''
;

byte =| '0' 'x' hex. hex. ;

hex =
| numeric.
| 'abcdef'
| 'ABCDEF'
;

del =| 0x7f ;
omega =| 0x7f 0x8f ;

simple =| 'a' 'b' ;