API Reference

Obtaining import-tree

As a flake input:

inputs.import-tree

inputs.import-tree.url = "github:vic/import-tree";

As a plain import:

let import-tree = import ./path-to/import-tree;

The resulting value is a callable attrset — the primary import-tree object.

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Core: Calling import-tree

import-tree <path | [paths]>

Takes a path or a (nested) list of paths. Returns a Nix module with imports set to all discovered files.

import-tree ./modules
import-tree [ ./modules ./extra ]
import-tree [ ./a [ ./b ] ]   # nested lists are flattened

Other import-tree objects can appear in the list as if they were paths.

Note

When the argument is an attrset with an options attribute, import-tree assumes it is being evaluated as a module. This lets a pre-configured import-tree object appear directly in imports.

Anything with an outPath attribute (like flake inputs) is treated as a path:

import-tree [ { outPath = ./modules; } ]

Non-path values (like attrsets) are passed through the filter and included if they pass.

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Filtering

.filter <fn>

fn : string -> bool — only include paths where fn returns true.

import-tree.filter (lib.hasInfix ".mod.") ./modules

Multiple .filter calls compose with AND.

.filterNot <fn>

Inverse of .filter — exclude paths where fn returns true.

import-tree.filterNot (lib.hasInfix "experimental") ./modules

.match <regex>

Include only paths matching the regex. Uses builtins.match (tests full string).

import-tree.match ".*/[a-z]+_[a-z]+\.nix" ./modules

Multiple .match calls compose with AND.

.matchNot <regex>

Exclude paths matching the regex.

import-tree.matchNot ".*/test_.*\.nix" ./modules

.initFilter <fn>

Replaces the default filter (.nix suffix, no /_ infix). Use for non-Nix files or custom ignore conventions.

import-tree.initFilter (lib.hasSuffix ".md") ./docs
import-tree.initFilter (p: lib.hasSuffix ".nix" p && !lib.hasInfix "/skip/" p)

Also applies to non-path items in import lists.

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Transformation

.map <fn>

fn : path -> a — transform each discovered path.

import-tree.map lib.traceVal ./modules        # trace each path
import-tree.map (p: { imports = [ p ]; })      # wrap in module
import-tree.map import                         # actually import

Multiple .map calls compose (first map runs first).

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Path Accumulation

.addPath <path>

Prepend a path to the internal path list. Can be called multiple times:

(import-tree.addPath ./vendor).addPath ./modules
# discovers files in both directories

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Extension

.addAPI <attrset>

Extend the import-tree object with new methods. Each value is a function receiving self (the current import-tree):

import-tree.addAPI {
  maximal = self: self.addPath ./all-modules;
  feature = self: name: self.filter (lib.hasInfix name);
}

Methods are late-bound — you can reference methods added in later .addAPI calls.

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Output

.withLib <lib>

Required before .leafs or .pipeTo when used outside module evaluation. Provides lib.filesystem.listFilesRecursive.

import-tree.withLib pkgs.lib

.leafs

Returns a configured import-tree that produces file lists instead of modules:

(import-tree.withLib lib).leafs ./modules
# => [ ./modules/a.nix ./modules/b.nix ]

.files

Shorthand for .leafs.result:

(import-tree.addPath ./modules).withLib lib |>.files

.pipeTo <fn>

Like .leafs but pipes the result list through fn:

(import-tree.withLib lib).pipeTo builtins.length ./modules
# => 3

.result

Evaluate with an empty path list. Equivalent to calling with []:

(import-tree.addPath ./modules).result

.new

Returns a fresh import-tree with empty state — no paths, filters, maps, or API extensions.

configured-tree.new  # back to a clean slate