bool lex_match_int (struct lexer *, int);
bool lex_at_phrase (struct lexer *, const char *s);
bool lex_match_phrase (struct lexer *, const char *s);
bool lex_match_int (struct lexer *, int);
bool lex_at_phrase (struct lexer *, const char *s);
bool lex_match_phrase (struct lexer *, const char *s);