img_err_cannot_find_fn_in_this_scope 在rust中也是一个{}之间为一个作用域。 是不是和别的语言差不多? 但其实rust中的函数还有一些自己的特点。 语句(statement)和表达式(expression)[2] 如果你学过babel[3],或者看过了解过ast(抽象语法树)。那么你应该看到过各种type: xxxExpression或者type: xxxStatem...
error[E0425]: cannot find function `foo_a_2` in this scope --> src/bin/main.rs:12:13 | 12 | foo_a_2(); | ^^^ not found in this scope | help: consider importing this function | 11 | use crate::a::foo_a_2; | error[E0425]: cannot find function `foo_a` in module `...
error[E0425]: cannot find function `test_two_sum` in this scope--> src/main.rs:2:5|2 | test_two_sum;| ^^^ not found in this scope For more information about this error, try `rustc --explain E0425`.error: could not compile `rust-lc` (bin "rust-lc") due to previous error...
("{b}") } // error[E0425]: cannot find value `b` in this scope // --> src/main.rs:6:16 // | // 6 | println!("{b}") // | ^ // | // help: the binding `b` is available in a different scope in the same function // --> src/main.rs:4:10 // | // 4 | ...
pub struct StrSplit{remainder:&str,delimiter:&str,}impl StrSplit{pub fnnew(haystack:&str,delimiter:&str)->Self{Self{remainder:haystack,delimiter,}}}impl IteratorforStrSplit{type Item=&str;fnnext(&mut self)->Option<Self::Item>{ifletSome(next_delim)=self.remainder.find(self.delimiter){letun...
// 这里编译器会报错`cannot findfunction`travel`inthis scope not foundinthis scope` // 原因是travel这个函数在闭包中并没有被申明 // 因此一种妥协的写法是: // see https://stackoverflow.com/questions/30559073/cannot-borrow-captured-outer-variable-in-an-fn-closure-as-mutable about why using `Ar...
error[E0433]: failed to resolve: use of undeclared type or module `futures`--> src/main.rs:4:5|4|use futures::executor::block_on;| ^^^use of undeclared type or module `futures`error[E0425]: cannot find function `block_on`inthisscope--> src/main.rs:12:5|12| block_on(future)...
error[E0425]:cannot findfunction`norm`inthisscope-->src/lib.rs:8:12|8|ifnorm(poly.center-point)<max_dist{|^^^not foundinthisscopeerror:aborting due to2previous errors]58/59:poly_match_rs 我们需要三个 crate 来实现我们的函数: 代码...
| ^^^ | = note: ...which immediately requires expanding type alias `int_type` again = note: type aliases cannot be recursive = help: consider using a struct, enum, or union instead to break the cycle = help: see <https://doc.rust-lang.org/reference/types.html#recursive-types> for...
That basically implies that we're going to find a str somewhere in the scope the reference to the u32 originated in, or somewhere _even earlier_. 即,需要一个`str`outlives`u32`,但这个`str`只能在函数体中产生,这是不可能的(因为即使产生,也会被自动 Drop 掉)。正确的做法是返回一个 String。