React应用编译失败：mathjs未导出eval的导入错误求助

云上老周

2026-5-6

Fixing "Attempted import error: 'eval' is not exported from 'mathjs'"

Hey there! I’ve run into this exact issue with mathjs before, so let’s get your calculator up and running again quickly.

What’s causing the error?

Starting with version 10.x of mathjs, the library renamed the eval method to evaluate. This change was made to avoid confusion with JavaScript’s native eval() function and to standardize the library’s API. Your code is trying to call math.eval(), which no longer exists in newer mathjs versions—hence the import error.

Quick, recommended fixes

Here are two straightforward ways to resolve this:

Update the method call in your code
Replace math.eval() with math.evaluate() in your handleEqual function. Here’s how that section should look after the change:
```
handleEqual = () => {
  this.setState({input: math.evaluate(this.state.input)});
}
```
evaluate() does the exact same job as the old eval()—it parses and computes your calculator’s input expression.

Optimize imports (optional)
If you want to reduce bundle size, you can import only the evaluate function instead of the entire mathjs library:

// Replace this line:
// import * as math from 'mathjs';
import { evaluate } from 'mathjs';

// Then use it directly in your handler:
handleEqual = () => {
  this.setState({input: evaluate(this.state.input)});
}