Formatter

Nanyx includes a standard formatter for producing consistent code layout across teams and projects.

The formatter focuses on whitespace, indentation, line wrapping, and other presentational concerns. It does not change program behavior.

The formatter is available as a command line tool and can be integrated into editor workflows.

The formatter is minimally configurable by design, with the goal of keeping style consistent across contributors and reducing formatting-only diffs in reviews. It also works well with analyzer guidance and editor tooling to help you write clean, idiomatic Nanyx code.

Why use it

• Keeps style consistent across contributors
• Reduces formatting-only diffs in reviews
• Works well with analyzer guidance and editor tooling

Usage modes

The formatter is available as a command within the Nanyx CLI. You can run it in different modes:

Check

Check mode verifies that files are already formatted according to the standard style. It exits with a non-zero status if any files would be changed by formatting.

# Check all files in the current working directory
nanyx format --check

# Check all files in the `src/` directory
nanyx format --check src/

# Check specific files
nanyx format --check src/file1.nyx src/file2.nyx

Write

Write mode applies formatting changes to the specified files. This is the default mode if no flags are provided.

# Format all files in the current working directory
nanyx format
# or
nanyx format --write

# Format all files in the `src/` directory
nanyx format src/

# Format specific files
nanyx format src/file1.nyx src/file2.nyx

Typical workflow

Format files before committing changes, and enable format-on-save in your editor where possible.

We also recommend adding a nanyx format --check step to your CI pipeline to ensure that all committed code adheres to the standard style when trying to merge a PR.

Examples

-- before
def add={a,b->a+b}

-- after
def add = { a, b -> a + b }

-- before
def Option.map: (#some(a) | r), (a -> b) -> (#some(b) | r) = { 
  | #some(a), f -> #some(f(a))
  | other, _ -> other }

-- after
def Option.map
  : (#some(a) | r), (a -> b) -> (#some(b) | r)
  = { | #some(a), f -> #some(f(a))
      | other, _ -> other }

Configuration

The formatter has a small set of configuration options that can be set in a [formatter] table of the package’s .nyxpack manifest. These options are intentionally limited to keep style consistent across contributors and projects.

[formatter]
# The maximum line width before wrapping occurs (default: 100)
lineWidth = 100
# The number of spaces to use for indentation (default: 2)
indentSize = 2

Related

See Official style analyzer for style diagnostics that complement formatting.