<<
#include <stdlib.h>
size_t mylexfn(p_context_t * context, p_token_info_t * out_token_info);
void record(int v);
>>

ptype int;

lex_fn mylexfn;

drop /\s+/;
token lbrace /\{/;
token rbrace /\}/;
token plus /\+/;
token macro;
token macroname /@[a-zA-Z_]\w*/;
token num /\d+/ << char b[100]; memcpy(b, match, match_length); b[match_length] = '\0'; $$ = atoi(b); >>

Start -> Statements;
Statements -> ;
Statements -> Statement Statements;
Statement -> Add;
Statement -> MacroStart;
Add -> num plus num << $$ = $1 + $3; record($$); >>
MacroStart -> macro macroname lbrace;