Common Errors & How to Fix Them

When something in your code needs attention, Pith points directly to the line and explains the problem in plain English.

error: cannot assign twice to immutable variable `score` (declare with `mut` to reassign)
  --> game.pi:3:1
   |
 3 | score = 20
   | ^

Here are the most common errors and how to solve them:

1. Changing a Variable Without `mut`

error: cannot assign twice to immutable variable `score` (declare with `mut` to reassign)

What it means: You created score = 10 and later tried to change it to score = 20.
How to fix it: Add mut when you first create the variable:
```
mut score = 10
score = 20    # Works!
```

error: `break` outside of a loop
error: `continue` outside of a loop

error: use of undeclared identifier `name`

What it means: Pith doesn’t recognize name.
How to fix it: Make sure you created the variable with name = "..." earlier in the code, or check for typos.

error: expected end of line between statements

What it means: You wrote two commands on the same line without pressing Enter.
How to fix it: Put each command on its own line:
```
# Instead of: x = 10 y = 20
x = 10
y = 20
```

error: literal is out of range for type u8 (maximum value is 255)

What it means: You gave a number larger than the maximum allowed by that type (like val: u8 = 300).
How to fix it: Use a smaller number, or remove the : u8 to let Pith handle the size automatically.

You may also see green or blue notes in the terminal:

note: private function is never referenced; eliminated: Pith noticed a function you wrote was never called, so it left it out to keep your program lean and fast.
note: unreachable exit path: A function returns early before reaching subsequent lines.