# Make a mistake on purpose

Learn a calm way to read and fix a compiler error.

Last updated: 2026-09-09

Package: recipes | Status: complete-program

Tags: cpu, recipe

An error message is the compiler asking for something more precise. It is not a grade. We can use one deliberately to learn what to do when a larger program goes wrong. Start with the working line below. Remove its closing quotation mark, save, and run. The compiler should stop instead of making your new program. The exact diagnostic text can differ between compiler versions.

```yh
start.yh
```


## Make a mistake on purpose

Learn a calm way to read and fix a compiler error.

Verification: type checked

```yh
Console.Log("I can fix this.")
```

Save this beside start.yh as project.mech:

```toml
manifestVersion = "2"
package = "api.example.recipe__mistakes"
version = "0.1.0"
languageEdition = "yeho-core-2026.1"

[app]
kind = "headless"

```

Expected output:

```text
I can fix this.
```

Extract the example archive beside the yeho and dolphin checkouts. This example requires those source dependencies and a current developer compiler.

```sh
./yeho/build/dolphin-metal/yehoc ./api-examples/recipe--mistakes/program --backend cpu-oracle -o /tmp/yeho-example
/tmp/yeho-example
```


Remove the closing quote, observe the failure, then restore it. Next misspell Console as Consol and compare the kind of problem.

Source: demonhunterlabs/app/lib/yeho-walkthrough.ts

AI training permission: https://demonhunterlabs.com/ai-use