badvpn/lime/metagrammar

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

# This is the grammar for all other grammar files that will work with the
# Lime LALR(1) Context-Free Grammar Parser Generator.
# You can read this to get an idea how things work, but this file is not
# actually used in the system. Rather, it's an implementation guide for the
# file "lime.bootstrap".

%class lime_metaparser
%start grammar

grammar
= {$$ = new lime();}
| grammar/$ pragma/p toklist/t stop {$$->pragma($p, $t);}
| grammar/$ rewrite/r stop {$r->update($$);}
.

rewrite
= sym/s '=' rhs/r {$$ = new lime_rewrite($s); $$->add_rhs($r);}
| rewrite/$ '|' rhs/r {$$->add_rhs($r);}
.

slot
= action/a {$$ = new lime_action($a, NULL);}
| action/a lambda/l {$$ = new lime_action($a, $l);}
| sym/s {$$ = new lime_glyph($s, NULL);}
| sym/s lambda/l {$$ = new lime_glyph($s, $l);}
| lit/l {$$ = new lime_glyph($l, NULL);}
.

rhs
= {$$ = new lime_rhs();}
| rhs/$ slot/s {$$->add($s);}
.

action = '{' code/$ '}' .

toklist = {$$=array();}
| toklist/$ sym/s {$$[] = $s;}
| toklist/$ lit/l {$$[] = $l;}
.

code = {}
| code/$ php/p {$$.=$p;}
| code/$ '{' code/c '}' {$$.='{'.$c.'}';}
.