%source { 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/*
static const char *dbg_str[] = { "Evaluating rule", "Matched rule", "Abandoning rule" };
#define PCC_DEBUG(auxil, event, rule, level, pos, buffer, length) \
    fprintf(stderr, "%*s%s %s @%zu [%.*s]\n", (int)((level) * 2), "", dbg_str[event], rule, pos, (int)(length), buffer)


*/
}



%common { 
#include "ast.h"

}

%value "AstNode" 

expr <- 
	  l:list { $$ = l; }
	/ n:number { $$ = n; }
	/ s:symbol { $$ = s; }
	/ t:string { $$ = t; }

list <- { $$ = astnode_new_list(); }
	'(' 
	( e:expr { astnode_append(&$$, e); }
	 )*
	')' _ 

number <- < [0-9]+ > (! ident_char) _  { $$ = astnode_new_num(atoi($1)); }
symbol <- < ident_char+ > _ { $$ = astnode_new_symbol(strdup($1)); }
string <- '"' < [^"]+ > '"' { $$ = astnode_new_string(strdup($1)); }

ident_char <- [-_a-zA-Z'+*0-9]
_ <- [ \t\n]*