E0308 rust type_error ai_generated true

error[E0308]: mismatched types: expected `usize`, found `f64`

ID: rust/e0308-expected-usize-found-float

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92%Fix Rate

88%Confidence

1Evidence

2023-06-15First Seen

Version Compatibility

Version	Status	Introduced	Deprecated	Notes
rustc 1.70.0	active	—	—	—
rustc 1.75.0	active	—	—	—
rustc 1.82.0	active	—	—	—

Assigning or passing a floating-point value where an unsigned integer index is required, often in array indexing or slice operations.

generic

在需要无符号整数索引的位置（如数组索引或切片操作）使用了浮点数。

85% success Use `as usize` to convert f64 to usize, ensuring the value is non-negative and within range: `let index = value as usize;`
```
Use `as usize` to convert f64 to usize, ensuring the value is non-negative and within range: `let index = value as usize;`
```
80% success Use `f64::round()` or `f64::floor()` before casting: `let index = value.round() as usize;`
```
Use `f64::round()` or `f64::floor()` before casting: `let index = value.round() as usize;`
```
90% success If the value is from user input or computation, parse or compute it as `usize` directly: `let index: usize = some_usize_source;`
```
If the value is from user input or computation, parse or compute it as `usize` directly: `let index: usize = some_usize_source;`
```

Use `as usize` to convert f64 to usize, ensuring the value is non-negative and within range: `let index = value as usize;`

Use `f64::round()` or `f64::floor()` before casting: `let index = value.round() as usize;`

If the value is from user input or computation, parse or compute it as `usize` directly: `let index: usize = some_usize_source;`

Common approaches that don't work:

45% fail
Truncation may cause logic errors; the compiler allows it but the behavior is undefined for negative or NaN values.
100% fail
Rust requires explicit conversion; this approach is syntactically invalid.
60% fail
If the value comes from a computation or input that yields f64, the type mismatch persists.