Struct starlark::eval::Arguments

pub struct Arguments<'v, 'a>(/* private fields */);

Arguments object is passed from the starlark interpreter to function implementation when evaluation function or method calls.

Implementations

impl<'v, 'a> Arguments<'v, 'a>

pub fn names_map(&self) -> Result<SmallMap<StringValue<'v>, Value<'v>>>

Unwrap all named arguments (both explicit and in **kwargs) into a map.

This operation fails if named argument names are not unique.

pub fn len(&self) -> Result<usize>

The number of arguments, where those inside a args/kwargs are counted as multiple arguments.

This operation fails if the kwargs is not a dictionary, or args does not support len.

pub fn names(&self) -> Result<Dict<'v>>

Unwrap all named arguments (both explicit and in **kwargs) into a dictionary.

This operation fails if named argument names are not unique.

pub fn positions<'b>( &'b self, heap: &'v Heap ) -> Result<impl Iterator<Item = Value<'v>> + 'b>

Unpack all positional parameters into an iterator.

pub fn unpack_kwargs(&self) -> Result<Option<DictRef<'v>>>

Examine the kwargs field, converting it to a Dict or failing. Note that even if this operation succeeds, the keys in the kwargs will not have been validated to be strings (as they must be). The arguments may also overlap with named, which would be an error.

pub fn unpack_kwargs_key(k: Value<'v>) -> Result<&'v str>

Confirm that a key in the kwargs field is indeed a string, or Err.

pub fn no_positional_args(&self, heap: &'v Heap) -> Result<()>

Produce Err if there are any positional arguments.

pub fn no_named_args(&self) -> Result<()>

Produce Err if there are any named (i.e. non-positional) arguments.

pub fn positional<const N: usize>( &self, heap: &'v Heap ) -> Result<[Value<'v>; N]>

Collect exactly N positional arguments from the Arguments, failing if there are too many/few arguments. Ignores named arguments.

pub fn optional<const REQUIRED: usize, const OPTIONAL: usize>( &self, heap: &'v Heap ) -> Result<([Value<'v>; REQUIRED], [Option<Value<'v>>; OPTIONAL])>

Collect exactly REQUIRED positional arguments, plus at most OPTIONAL positional arguments from the Arguments, failing if there are too many/few arguments. Ignores named arguments. The OPTIONAL array will never have a Some after a None.

pub fn positional1(&self, heap: &'v Heap) -> Result<Value<'v>>

Collect 1 positional arguments from the Arguments, failing if there are too many/few arguments. Ignores named arguments.

pub fn optional1(&self, heap: &'v Heap) -> Result<Option<Value<'v>>>

Collect up to 1 optional arguments from the Arguments, failing if there are too many arguments. Ignores named arguments.

impl Arguments<'_, '_>

pub fn check_this<'v, T: UnpackValue<'v>>(this: Value<'v>) -> Result<T>

Utility for checking a this parameter matches what you expect.

pub fn check_required<'v, T: UnpackValue<'v>>( name: &str, x: Option<Value<'v>> ) -> Result<T>

Utility for checking a required parameter matches what you expect.

pub fn check_optional<'v, T: UnpackValue<'v>>( name: &str, x: Option<Value<'v>> ) -> Result<Option<T>>

Utility for checking an optional parameter matches what you expect.

Trait Implementations

impl<'v, 'a> Clone for Arguments<'v, 'a>

fn clone(&self) -> Arguments<'v, 'a>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'v, 'a> Default for Arguments<'v, 'a>

fn default() -> Arguments<'v, 'a>

Returns the “default value” for a type.

impl<'v, 'a> Dupe for Arguments<'v, 'a>

fn dupe(&self) -> Self