args

Module nu.lang.args.

Argument type aliases for Nu kind class signatures.

A kind that takes a python int (or a Nu that yields one) declares its slot type as IntArg rather than spelling int | Nu | Sentinel each time. The aliases keep concrete kind signatures short and readable while still admitting the full algebraic surface (a raw python value, a Nu sub-tree producing one, or a propagating sentinel).

Each specialized alias also admits Any explicitly: the honest terminal is consumable everywhere. This is redundant with the TypedNu [Any]` variance trick (`Nu[Any]` already substitutes for `Nu[int] etc.), but stating it in the alias makes the surface readable in code - you can see at a glance that IntArg welcomes a dynamic value.

Arg[T] is the generic form. The specialized aliases (IntArg, StrArg, ...) cover the common scalar and collection cases.

Import note: Any lives in nu.forms which imports from nu.lang, so a runtime import here would cycle. PEP 695 type aliases evaluate their RHS lazily (TypeAliasType.__value__ is only touched by mypy or explicit introspection), so a TYPE_CHECKING-only import is sufficient: mypy sees the name, runtime never does.

Arg

Create named, parameterized type aliases.

lang.Arg()

Path nu.lang.Arg. Defined on nu.lang.args, bound as a function.

This provides a backport of the new type statement in Python 3.12:

type ListOrSet[T] = list[T] | set[T]

is equivalent to:

T = TypeVar("T")
ListOrSet = TypeAliasType("ListOrSet", list[T] | set[T], type_params=(T,))

The name ListOrSet can then be used as an alias for the type it refers to.

The type_params argument should contain all the type parameters used in the value of the type alias. If the alias is not generic, this argument is omitted.

Static type checkers should only support type aliases declared using TypeAliasType that follow these rules:

• The first argument (the name) must be a string literal.
• The TypeAliasType instance must be immediately assigned to a variable of the same name. (For example, 'X = TypeAliasType("Y", int)' is invalid, as is 'X, Y = TypeAliasType("X", int), TypeAliasType("Y", int)').

Undocumented: yields, example.

DictArg

Create named, parameterized type aliases.

lang.DictArg()

Path nu.lang.DictArg. Defined on nu.lang.args, bound as a function.

This provides a backport of the new type statement in Python 3.12:

type ListOrSet[T] = list[T] | set[T]

is equivalent to:

T = TypeVar("T")
ListOrSet = TypeAliasType("ListOrSet", list[T] | set[T], type_params=(T,))

The name ListOrSet can then be used as an alias for the type it refers to.

The type_params argument should contain all the type parameters used in the value of the type alias. If the alias is not generic, this argument is omitted.

Static type checkers should only support type aliases declared using TypeAliasType that follow these rules:

• The first argument (the name) must be a string literal.
• The TypeAliasType instance must be immediately assigned to a variable of the same name. (For example, 'X = TypeAliasType("Y", int)' is invalid, as is 'X, Y = TypeAliasType("X", int), TypeAliasType("Y", int)').

Undocumented: yields, example.

FrozenSetArg

Create named, parameterized type aliases.

lang.FrozenSetArg()

Path nu.lang.FrozenSetArg. Defined on nu.lang.args, bound as a function.

This provides a backport of the new type statement in Python 3.12:

type ListOrSet[T] = list[T] | set[T]

is equivalent to:

T = TypeVar("T")
ListOrSet = TypeAliasType("ListOrSet", list[T] | set[T], type_params=(T,))

The name ListOrSet can then be used as an alias for the type it refers to.

The type_params argument should contain all the type parameters used in the value of the type alias. If the alias is not generic, this argument is omitted.

Static type checkers should only support type aliases declared using TypeAliasType that follow these rules:

• The first argument (the name) must be a string literal.
• The TypeAliasType instance must be immediately assigned to a variable of the same name. (For example, 'X = TypeAliasType("Y", int)' is invalid, as is 'X, Y = TypeAliasType("X", int), TypeAliasType("Y", int)').

Undocumented: yields, example.

ListArg

Create named, parameterized type aliases.

lang.ListArg()

Path nu.lang.ListArg. Defined on nu.lang.args, bound as a function.

This provides a backport of the new type statement in Python 3.12:

type ListOrSet[T] = list[T] | set[T]

is equivalent to:

T = TypeVar("T")
ListOrSet = TypeAliasType("ListOrSet", list[T] | set[T], type_params=(T,))

The name ListOrSet can then be used as an alias for the type it refers to.

The type_params argument should contain all the type parameters used in the value of the type alias. If the alias is not generic, this argument is omitted.

Static type checkers should only support type aliases declared using TypeAliasType that follow these rules:

• The first argument (the name) must be a string literal.
• The TypeAliasType instance must be immediately assigned to a variable of the same name. (For example, 'X = TypeAliasType("Y", int)' is invalid, as is 'X, Y = TypeAliasType("X", int), TypeAliasType("Y", int)').

Undocumented: yields, example.

SetArg

Create named, parameterized type aliases.

lang.SetArg()

Path nu.lang.SetArg. Defined on nu.lang.args, bound as a function.

This provides a backport of the new type statement in Python 3.12:

type ListOrSet[T] = list[T] | set[T]

is equivalent to:

T = TypeVar("T")
ListOrSet = TypeAliasType("ListOrSet", list[T] | set[T], type_params=(T,))

The name ListOrSet can then be used as an alias for the type it refers to.

The type_params argument should contain all the type parameters used in the value of the type alias. If the alias is not generic, this argument is omitted.

Static type checkers should only support type aliases declared using TypeAliasType that follow these rules:

• The first argument (the name) must be a string literal.
• The TypeAliasType instance must be immediately assigned to a variable of the same name. (For example, 'X = TypeAliasType("Y", int)' is invalid, as is 'X, Y = TypeAliasType("X", int), TypeAliasType("Y", int)').

Undocumented: yields, example.

TupleArg

Create named, parameterized type aliases.

lang.TupleArg()

Path nu.lang.TupleArg. Defined on nu.lang.args, bound as a function.

This provides a backport of the new type statement in Python 3.12:

type ListOrSet[T] = list[T] | set[T]

is equivalent to:

T = TypeVar("T")
ListOrSet = TypeAliasType("ListOrSet", list[T] | set[T], type_params=(T,))

The name ListOrSet can then be used as an alias for the type it refers to.

The type_params argument should contain all the type parameters used in the value of the type alias. If the alias is not generic, this argument is omitted.

Static type checkers should only support type aliases declared using TypeAliasType that follow these rules:

• The first argument (the name) must be a string literal.
• The TypeAliasType instance must be immediately assigned to a variable of the same name. (For example, 'X = TypeAliasType("Y", int)' is invalid, as is 'X, Y = TypeAliasType("X", int), TypeAliasType("Y", int)').

Undocumented: yields, example.