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Modules and Imports

Duckstruct programs can be split across multiple .ds files.

Projects and entrypoints​

A typical project contains:

  • duckstruct.toml (manifest)
  • src/main.ds (entrypoint by convention)

ds init creates this layout for you.

Import syntax​

Imports use use:

use helper::{ONE, double};

Imported symbols must be exported from the module with pub:

pub let ONE = 1;
pub f double(x) { x + x }

root:: imports (project modules)​

When compiling a project (a directory containing duckstruct.toml), you can import modules relative to the project root using root:::

use root::lib::util::{VAL};

This corresponds to a file like lib/util.ds at the project root.

root:: requires a manifest; compiling a single file without a project cannot resolve root:: imports.

Builtin modules​

Some module names are reserved for the standard library. For example, file is a builtin module, not a local file.ds on disk:

use file::{read};

Tips​

  • Prefer root::... for anything that is not adjacent to the entry file.
  • Keep module cycles in mind: circular imports are rejected.