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AttrPath

Definition

NonEmpty KeyName

Description

AttrPath represents a path to an attribute in an attribute set, like foo.bar.baz. An attribute path must be non-empty: it always contains at least one key.

Nix Source ↔ AST

{
  "tag": "NamedVar",
  "attrPath": [
    { "tag": "StaticKey", "contents": "foo" },
    { "tag": "StaticKey", "contents": "bar" }
  ],
  "value": { ... }
}

Examples

foo.bar.baz
  → [ StaticKey "foo", StaticKey "bar", StaticKey "baz" ]

"${name}.static"
  → [ DynamicKey (Antiquoted (Sym "name")), StaticKey "static" ]

Used as the attrPath field of:

  • NamedVar: binding left-hand side
  • Select: attribute selection
  • HasAttr: attribute existence check

Nix Library Access

syntax.mkStaticKey "foo"
syntax.mkDynamicKey (syntax.mkAntiquoted (syntax.mkSym "name"))