hdl.ast: Add AnyConst and AnySeq value types.

nmigen/__init__.py

@@ -1,4 +1,4 @@
-from .hdl.ast import Value, Const, C, Mux, Cat, Repl, Array, Signal, ClockSignal, ResetSignal, Assert, Assume
+from .hdl.ast import Value, Const, C, AnyConst, AnySeq, Mux, Cat, Repl, Array, Signal, ClockSignal, ResetSignal, Assert, Assume
 from .hdl.dsl import Module
 from .hdl.cd import ClockDomain
 from .hdl.ir import Fragment, Instance

nmigen/hdl/ast.py

@@ -9,7 +9,7 @@ from ..tools import *
 
 
 __all__ = [
-    "Value", "Const", "C", "Operator", "Mux", "Part", "Slice", "Cat", "Repl",
+    "Value", "Const", "C", "AnyConst", "AnySeq", "Operator", "Mux", "Part", "Slice", "Cat", "Repl",
     "Array", "ArrayProxy",
     "Signal", "ClockSignal", "ResetSignal",
     "Statement", "Assign", "Assert", "Assume", "Switch", "Delay", "Tick",
@@ -254,6 +254,32 @@ class Const(Value):
 C = Const  # shorthand
 
 
+class AnyValue(Value):
+    def __init__(self, shape):
+        super().__init__(src_loc_at=0)
+        if isinstance(shape, int):
+            shape = shape, False
+        self.nbits, self.signed = shape
+        if not isinstance(self.nbits, int) or self.nbits < 0:
+            raise TypeError("Width must be a non-negative integer, not '{!r}'", self.nbits)
+
+    def shape(self):
+        return self.nbits, self.signed
+
+    def _rhs_signals(self):
+        return ValueSet()
+
+
+class AnyConst(AnyValue):
+    def __repr__(self):
+        return "(anyconst {}'{})".format(self.nbits, "s" if self.signed else "")
+
+
+class AnySeq(AnyValue):
+    def __repr__(self):
+        return "(anyseq {}'{})".format(self.nbits, "s" if self.signed else "")
+
+
 class Operator(Value):
     def __init__(self, op, operands, src_loc_at=0):
         super().__init__(src_loc_at=1 + src_loc_at)