Implement RFC 35: Add ShapeLike, ValueLike.

docs/lang.rst

@@ -121,14 +121,14 @@ The shape of the constant can be specified explicitly, in which case the number'
    0
 
 
-.. _lang-shapecasting:
+.. _lang-shapelike:
 
 Shape casting
 =============
 
-Shapes can be *cast* from other objects, which are called *shape-castable*. Casting is a convenient way to specify a shape indirectly, for example, by a range of numbers representable by values with that shape.
+Shapes can be *cast* from other objects, which are called *shape-like*. Casting is a convenient way to specify a shape indirectly, for example, by a range of numbers representable by values with that shape.
 
-Casting to a shape can be done explicitly with ``Shape.cast``, but is usually implicit, since shape-castable objects are accepted anywhere shapes are.
+Casting to a shape can be done explicitly with ``Shape.cast``, but is usually implicit, since shape-like objects are accepted anywhere shapes are.
 
 
 .. _lang-shapeint:
@@ -244,16 +244,16 @@ The :mod:`amaranth.lib.enum` module extends the standard enumerations such that
    The enumeration does not have to subclass :class:`enum.IntEnum` or have :class:`int` as one of its base classes; it only needs to have integers as values of every member. Using enumerations based on :class:`enum.Enum` rather than :class:`enum.IntEnum` prevents unwanted implicit conversion of enum members to integers.
 
 
-.. _lang-valuecasting:
+.. _lang-valuelike:
 
 Value casting
 =============
 
-Like shapes, values may be *cast* from other objects, which are called *value-castable*. Casting to values allows objects that are not provided by Amaranth, such as integers or enumeration members, to be used in Amaranth expressions directly.
+Like shapes, values may be *cast* from other objects, which are called *value-like*. Casting to values allows objects that are not provided by Amaranth, such as integers or enumeration members, to be used in Amaranth expressions directly.
 
 .. TODO: link to ValueCastable
 
-Casting to a value can be done explicitly with ``Value.cast``, but is usually implicit, since value-castable objects are accepted anywhere values are.
+Casting to a value can be done explicitly with ``Value.cast``, but is usually implicit, since value-like objects are accepted anywhere values are.
 
 
 Values from integers
@@ -343,7 +343,7 @@ A *signal* is a value representing a (potentially) varying number. Signals can b
 Signal shapes
 -------------
 
-A signal can be created with an explicitly specified shape (any :ref:`shape-castable <lang-shapecasting>` object); if omitted, the shape defaults to ``unsigned(1)``. Although rarely useful, 0-bit signals are permitted.
+A signal can be created with an explicitly specified shape (any :ref:`shape-like <lang-shapelike>` object); if omitted, the shape defaults to ``unsigned(1)``. Although rarely useful, 0-bit signals are permitted.
 
 .. doctest::
 
@@ -444,7 +444,7 @@ Amaranth provides aggregate data structures in the standard library module :mod:
 Operators
 =========
 
-To describe computations, Amaranth values can be combined with each other or with :ref:`value-castable <lang-valuecasting>` objects using a rich array of arithmetic, bitwise, logical, bit sequence, and other *operators* to form *expressions*, which are themselves values.
+To describe computations, Amaranth values can be combined with each other or with :ref:`value-like <lang-valuelike>` objects using a rich array of arithmetic, bitwise, logical, bit sequence, and other *operators* to form *expressions*, which are themselves values.
 
 
 .. _lang-abstractexpr:

docs/stdlib/data.rst

@@ -61,7 +61,7 @@ While this implementation works, it is repetitive, error-prone, hard to read, an
 
     m.d.comb += o_gray.eq((i_color.red + i_color.green + i_color.blue) << 1)
 
-The :class:`View` is :ref:`value-castable <lang-valuecasting>` and can be used anywhere a plain value can be used. For example, it can be assigned to in the usual way:
+The :class:`View` is :ref:`value-like <lang-valuelike>` and can be used anywhere a plain value can be used. For example, it can be assigned to in the usual way:
 
 .. testcode::
 
@@ -135,7 +135,7 @@ In case the data has related operations or transformations, :class:`View` can be
         def brightness(self):
             return (self.red + self.green + self.blue)[-8:]
 
-Here, the ``RGBLayout`` class itself is :ref:`shape-castable <lang-shapecasting>` and can be used anywhere a shape is accepted. When a :class:`Signal` is constructed with this layout, the returned value is wrapped in an ``RGBView``:
+Here, the ``RGBLayout`` class itself is :ref:`shape-like <lang-shapelike>` and can be used anywhere a shape is accepted. When a :class:`Signal` is constructed with this layout, the returned value is wrapped in an ``RGBView``:
 
 .. doctest::
 

docs/stdlib/enum.rst

@@ -59,7 +59,7 @@ The ``shape=`` argument is optional. If not specified, classes from this module
 
 In this way, this module is a drop-in replacement for the standard :mod:`enum` module, and in an Amaranth project, all ``import enum`` statements may be replaced with ``from amaranth.lib import enum``.
 
-Signals with :class:`Enum` or :class:`Flag` based shape are automatically wrapped in the :class:`EnumView` or :class:`FlagView` value-castable wrappers, which ensure type safety. Any :ref:`value-castable <lang-valuecasting>` can also be explicitly wrapped in a view class by casting it to the enum type:
+Signals with :class:`Enum` or :class:`Flag` based shape are automatically wrapped in the :class:`EnumView` or :class:`FlagView` value-like wrappers, which ensure type safety. Any :ref:`value-like <lang-valuelike>` can also be explicitly wrapped in a view class by casting it to the enum type:
 
 .. doctest::