Enum Action 

#[non_exhaustive]
pub enum Action {
    Symlink(SymlinkArgs),
    Unlink(UnlinkArgs),
    Env(EnvArgs),
    Mkdir(MkdirArgs),
    Rmdir(RmdirArgs),
    Require(RequireSpec),
    When(WhenSpec),
    Exec(ExecSpec),
}

One entry in a pack’s actions: (or teardown:) list.

Marked #[non_exhaustive] because M4 ships plugin-contributed action kinds; external match sites must carry a _ arm so the Tier-1 registry can grow without a major-version bump.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Symlink(SymlinkArgs)

symlink primitive.

Unlink(UnlinkArgs)

Synthesized inverse of symlink for auto-reverse teardown (R-M5-09). Not a YAML-parseable action.

Env(EnvArgs)

env primitive.

Mkdir(MkdirArgs)

mkdir primitive.

Rmdir(RmdirArgs)

rmdir primitive.

Require(RequireSpec)

require gate.

When(WhenSpec)

when conditional block.

Exec(ExecSpec)

exec shell escape.

Implementations

impl Action

pub fn from_yaml(value: &Value) -> Result<Self, PackParseError>

Parse a single action entry from a YAML value.

Rejects zero-key and multi-key entries with PackParseError::EmptyActionEntry / PackParseError::MultipleActionKeys, and unknown keys with PackParseError::UnknownActionKey.

pub fn parse_list(value: Option<&Value>) -> Result<Vec<Self>, PackParseError>

Parse an entire actions: sequence.

pub fn name(&self) -> &'static str

Short kebab-case identifier matching the YAML key that produced this variant (and the name plugins register under). Returned as &'static str so callers can zero-cost compare against constants like ACTION_SYMLINK (defined in the execute::step module).

pub fn iter_symlinks(&self) -> Box<dyn Iterator<Item = &SymlinkArgs> + '_>

Walk this action (and any nested when.actions) yielding every SymlinkArgs reached.

• Action::Symlink yields the wrapped args.
• Action::When recurses into when.actions (which themselves may be when blocks — recursion is unbounded because the parse-time depth bound applies to predicate trees, not action nesting; in practice authors do not nest when deeply, and validators consume whatever the parser accepted).
• Every other variant yields an empty iterator.

The iterator is boxed so variant-specific concrete iterator types can share a single return shape. Boxing cost is negligible against the outer YAML parse and well-bounded action lists; swapping to a custom enum-iterator later is YAGNI for now.

Trait Implementations

impl Clone for Action

fn clone(&self) -> Action

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Action

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for Action

fn eq(&self, other: &Action) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for Action

impl StructuralPartialEq for Action