| SOURCE_FILE | |
| FN | |
| FN_KW "fn" | |
| WHITESPACE " " | |
| NAME | |
| IDENT "f" | |
| PARAM_LIST | |
| L_PAREN "(" | |
| R_PAREN ")" | |
| WHITESPACE " " | |
| RET_TYPE | |
| THIN_ARROW "->" | |
| WHITESPACE " " | |
| IMPL_TRAIT_TYPE | |
| IMPL_KW "impl" | |
| WHITESPACE " " | |
| TYPE_BOUND_LIST | |
| TYPE_BOUND | |
| PATH_TYPE | |
| PATH | |
| PATH_SEGMENT | |
| NAME_REF | |
| IDENT "Iterator" | |
| GENERIC_ARG_LIST | |
| L_ANGLE "<" | |
| ASSOC_TYPE_ARG | |
| NAME_REF | |
| IDENT "Item" | |
| WHITESPACE " " | |
| EQ "=" | |
| WHITESPACE " " | |
| COMMA "," | |
| WHITESPACE " " | |
| ASSOC_TYPE_ARG | |
| NAME_REF | |
| IDENT "Item" | |
| WHITESPACE " " | |
| EQ "=" | |
| WHITESPACE " " | |
| R_ANGLE ">" | |
| WHITESPACE " " | |
| BLOCK_EXPR | |
| STMT_LIST | |
| L_CURLY "{" | |
| R_CURLY "}" | |
| WHITESPACE "\n" | |
| error 30: missing associated item binding | |
| error 39: missing associated item binding |