feat(qsystem): add RNG.random_advance()

guppylang-internals/pyproject.toml

@@ -38,6 +38,9 @@ dependencies = [
     "hugr ~= 0.13.1",
 ]
 
+[tool.uv.sources]
+tket-exts = { git = "https://github.com/CQCL/tket2", subdirectory = "tket-exts", rev = "eed16e8" }
+
 [project.optional-dependencies]
 pytket = ["pytket>=1.34"]
 

guppylang/src/guppylang/std/qsystem/random.py

@@ -73,6 +73,16 @@ def random_int_bounded(self: "RNG", bound: int) -> int:
             bound: The upper bound of the range, needs to less than 2^31.
         """
 
+    @hugr_op(external_op("RandomAdvance", [], ext=QSYSTEM_RANDOM_EXTENSION))
+    @no_type_check
+    def random_advance(self: "RNG", delta: int) -> None:
+        """Advance or backtrack the RNG state by a given number of steps.
+
+        Args:
+            delta: Number of steps to move the RNG state forward (if positive)
+            or backward (if negative).
+        """
+
     @guppy
     @no_type_check
     def shuffle(self: "RNG", array: array[SHUFFLE_T, SHUFFLE_N]) -> None:

tests/integration/test_qsystem.py

@@ -46,6 +46,8 @@ def test() -> tuple[int, float, int, int, angle, angle]:
         rint = rng.random_int()
         rfloat = rng.random_float()
         rint_bnd = rng.random_int_bounded(100)
+        rng.random_advance(-1)
+        rint_bnd = rng.random_int_bounded(100)
         ar = array(qubit() for _ in range(5))
         rng.shuffle(ar)
         _ = measure_array(ar)