f-string is missing placeholders
时间: 2023-09-03 16:15:51 浏览: 101
This error message typically occurs when an f-string is missing one or more placeholders. A placeholder is a pair of curly braces `{}` inside the f-string that indicates where a value should be inserted.
For example, in the following f-string, there are two placeholders that expect values to be inserted:
```
name = "Alice"
age = 30
print(f"My name is {name} and I am {age} years old.")
```
If a placeholder is missing, you will get an error like this:
```
ValueError: f-string is missing placeholders
```
To fix the error, make sure that every placeholder in the f-string has a corresponding value to be inserted.
相关问题
placeholders
"std::placeholders::_1" 是 C++ STL (标准模板库) 中的一个占位符(placeholder),用于在使用std::bind函数时表示第一个参数的位置。
例如,如果我们有一个函数`void func(int a, int b)`,我们可以使用std::bind将其绑定到另一个函数并固定第一个参数的值。这可以通过以下代码实现:
```
auto bind_func = std::bind(func, std::placeholders::_1, 5);
```
在这里,`std::placeholders::_1` 代表函数调用时第一个参数的位置,这意味着我们只需要提供第二个参数即可调用 `bind_func`,例如:`bind_func(10)` 将调用 `func(10, 5)`。
Required URI template variable 'name' for method parameter type String is not present]
This error message is indicating that the URI template variable 'name' is missing from the API request.
URI template variables are placeholders in the URI path that can be replaced with actual values in a request. For example, in the URI path "/users/{name}", the variable "name" can be replaced with an actual user name in a request.
To resolve this error, make sure that the URI template variable 'name' is included in the API request and that it has a valid value. This may involve checking the API documentation or reviewing the code that is generating the API request.