error: expected a pattern range bound, found an expression --> $DIR/pat-ranges-3.rs:4:16 | LL | let 10 ..= 10 + 3 = 12; | ^^^^^^ not a pattern | = note: arbitrary expressions are not allowed in patterns: error: expected a pattern range bound, found an expression --> $DIR/pat-ranges-3.rs:7:9 | LL | let 10 - 3 ..= 10 = 8; | ^^^^^^ not a pattern | = note: arbitrary expressions are not allowed in patterns: error: aborting due to 2 previous errors