Linter (cm lint)

Cm has a built-in static analysis tool (Linter). It detects code quality issues and provides improvement hints.

Basic Usage

# Check a single file
./cm lint src/main.cm

# Recursively check a directory
./cm lint src/

Check Items

1. Naming Conventions

Cm recommends the following naming conventions:

Target Convention Example
Variables/Functions snake_case my_variable, calc_sum
Types/Structs PascalCase MyStruct, HttpClient
Constants SCREAMING_SNAKE_CASE MAX_SIZE, PI 
// ⚠️ Warning: variable names should use snake_case
int myVariable = 10;  // → my_variable

// ✅ OK
int my_variable = 10;

2. Unused Variables

Detects variables that are not used:

int main() {
    int x = 10;  // ⚠️ Warning: variable 'x' is unused
    return 0;
}

3. const Suggestions

Suggests const for variables that are not modified:

int main() {
    int size = 100;  // ⚠️ Warning: 'size' can be const
    println("Size: {size}");
    return 0;
}

Configuration File (.cmlint.yml)

Place .cmlint.yml in project root to configure rules:

# Enable naming convention checks
naming:
  enabled: true
  variables: snake_case
  types: PascalCase

# Enable unused variable checks
unused:
  enabled: true
  warn_unused_params: false  # Don't warn about unused parameters

# Disable const suggestions
const_suggestion:
  enabled: false

Output Example

warning: variable 'myValue' should use snake_case naming
  --> src/main.cm:5:9
  |
5 |     int myValue = 10;
  |         ^^^^^^^
  |
  = help: consider renaming to 'my_value'

warning: unused variable 'x'
  --> src/main.cm:8:9
  |
8 |     int x = 42;
  |         ^
  |

Last Updated: 2026-02-08