Enum OsFunctionCall 

pub enum OsFunctionCall {
    Exists(MontyPath),
    IsFile(MontyPath),
    IsDir(MontyPath),
    IsSymlink(MontyPath),
    ReadText(MontyPath),
    ReadBytes(MontyPath),
    Stat(MontyPath),
    Iterdir(MontyPath),
    Resolve(MontyPath),
    Absolute(MontyPath),
    WriteText(PathStringDataArgs),
    AppendText(PathStringDataArgs),
    WriteBytes(PathBytesDataArgs),
    AppendBytes(PathBytesDataArgs),
    Open(OpenCallArgs),
    Mkdir(MkdirCallArgs),
    Unlink(MontyPath),
    Rmdir(MontyPath),
    Rename(RenameCallArgs),
    Getenv(GetenvArgs),
    GetEnviron,
    DateToday,
    DateTimeNow(Option<MontyTimeZone>),
}

Tagged dispatch value for OS-level operations.

Each variant carries the strongly-typed args/kwargs the corresponding OS call needs. The fs/ layer matches on this enum directly (no MontyObject introspection); host bindings get a generic (positional, keyword) view via OsFunctionCall::to_args.

See the module docs for how to add a new variant.

Variants

Exists(MontyPath)

Check if a path exists.

IsFile(MontyPath)

Check if path is a regular file.

IsDir(MontyPath)

Check if path is a directory.

IsSymlink(MontyPath)

Check if path is a symbolic link.

ReadText(MontyPath)

Read file contents as text.

ReadBytes(MontyPath)

Read file contents as bytes.

Stat(MontyPath)

stat() — return a stat result tuple.

Iterdir(MontyPath)

List directory contents.

Resolve(MontyPath)

Resolve symlinks and return absolute path.

Absolute(MontyPath)

Absolute path without symlink resolution.

WriteText(PathStringDataArgs)

Write text to file (truncating).

AppendText(PathStringDataArgs)

Append text to file.

WriteBytes(PathBytesDataArgs)

Write bytes to file (truncating).

AppendBytes(PathBytesDataArgs)

Append bytes to file.

Open(OpenCallArgs)

Open a file. The host performs the open-time effect (truncate for w/w+, create-if-missing for a/a+, existence check for r/r+) and returns a MontyObject::FileHandle — it never holds a live OS handle across calls.

Mkdir(MkdirCallArgs)

Create directory (parents/exist_ok kwargs).

Unlink(MontyPath)

Remove file.

Rmdir(MontyPath)

Remove directory.

Rename(RenameCallArgs)

Rename / move (src → dst).

Getenv(GetenvArgs)

Get an environment variable value.

GetEnviron

Get the entire environment as a dictionary.

DateToday

Get today’s date from the host system (for date.today()).

DateTimeNow(Option<MontyTimeZone>)

Get the current date/time from the host system (for datetime.now(tz=...)). Carries the timezone argument, None for a naive result.

Implementations

impl OsFunctionCall

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

Stable string name for this OS function — surfaces in Self::on_no_handler errors, host os callbacks, and serialised snapshots. The strum serialize string on each variant.

pub fn to_args(self) -> (Vec<MontyObject>, Vec<(MontyObject, MontyObject)>)

Projects this call’s args into (positional, keyword) MontyObject vectors for delivery to a host callback.

pub fn is_write(&self) -> bool

Whether this call mutates filesystem state — the read-only-mount gate. Open’s write-ness is mode-dependent (w/w+/a/a+ write; r/r+ don’t).

pub fn is_existence_check(&self) -> bool

Whether this operation checks existence without reading content. Existence checks return false for nonexistent paths rather than raising FileNotFoundError, matching CPython’s pathlib.Path.

pub fn embedded_null_message(&self, for_destination: bool) -> &'static str

CPython’s ValueError message for a path containing a null byte.

The wording is not uniform in CPython: it comes from whichever layer first inspects the path, so the content operations go through open() and say embedded null byte, while the metadata ones are named by the syscall their os wrapper was about to make. for_destination picks the rename argument that carried the byte.

pub fn fs_primary_path(&self) -> Option<&str>

The call’s primary path if it’s a FS operation, None otherwise.

Used for routing and error reporting.

pub fn rename_destination(&self) -> Option<&str>

The rename destination path, or None for every other variant — the second routing key a mount table needs (both rename endpoints must resolve to the same mount).

pub fn on_no_handler(&self) -> MontyException

Exception to raise when no handler accepted this call: PermissionError for FS ops (with the path), RuntimeError for non-FS ops.

Trait Implementations

impl Clone for OsFunctionCall

fn clone(&self) -> OsFunctionCall

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OsFunctionCall

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for OsFunctionCall

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for OsFunctionCall

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

Formats the value using the given formatter.

impl<'_derivative_strum> From<&'_derivative_strum OsFunctionCall> for &'static str

fn from(x: &'_derivative_strum OsFunctionCall) -> &'static str

Converts to this type from the input type.

impl From<OsFunctionCall> for &'static str

fn from(x: OsFunctionCall) -> &'static str

Converts to this type from the input type.

impl Serialize for OsFunctionCall

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.