Bloq namespacing and display (__str__) updates. (#1825)

As part of #1824 , I want to be better about our convention for
importing bloqs and `__str__` representations in the qualtran standard
library (i.e. `qualtran.bloqs`). There's no additional restriction on
custom, user-authored bloqs. These changes make sure:

- bloqs are generally imported "one level up" from their file. e.g.
`ControlledAddOrSubtract` is defined in
`qualtran/bloqs/arithmetic/controlled_add_or_subtract.py` but it prefers
to be imported from `qualtran.bloqs.arithmetic`. This is codified in the
(existing) default `_pkg_(cls) -> str` classmethod. You can override it
if you want something different.
- The `__str__` representation looks like an object string (cc #1823).
This PR removes some special symbols in favor of more Python-looking
strings.

note that this causes more bloq examples to be loadable (visible in the
re-generated manifest)

Author: mpharrigan

qualtran/bloqs/arithmetic/__init__.py

@@ -29,6 +29,7 @@
     LinearDepthHalfLessThanEqual,
     SingleQubitCompare,
 )
+from qualtran.bloqs.arithmetic.controlled_add_or_subtract import ControlledAddOrSubtract
 from qualtran.bloqs.arithmetic.controlled_addition import CAdd
 from qualtran.bloqs.arithmetic.conversions import (
     SignedIntegerToTwosComplement,

qualtran/bloqs/arithmetic/addition.py

@@ -480,6 +480,9 @@ def build_call_graph(self, ssa: 'SympySymbolAllocator') -> 'BloqCountDictT':
 
         return counts
 
+    def __str__(self):
+        return f'AddK(k={self.k})'
+
 
 @bloq_example(generalizer=ignore_split_join)
 def _add_k() -> AddK:

qualtran/bloqs/arithmetic/addition_test.py

@@ -449,3 +449,8 @@ def test_controlled_add_from_add():
     assert ctrl == 0
     assert a == 5
     assert b == 15
+
+
+def test_add_k_str():
+    add_k = AddK(QUInt(5), k=3)
+    assert str(add_k) == "AddK(k=3)"

qualtran/bloqs/arithmetic/bitwise.py

@@ -231,6 +231,9 @@ def on_classical_vals(self, x: 'ClassicalValT') -> Dict[str, 'ClassicalValT']:
             x %= 2**self.dtype.bitsize
         return {'x': x}
 
+    def __str__(self):
+        return f'BitwiseNot({self.dtype.num_bits})'
+
 
 @bloq_example
 def _bitwise_not() -> BitwiseNot:

qualtran/bloqs/arithmetic/bitwise_test.py

@@ -184,3 +184,8 @@ def test_bitwisenot_classical_action(dtype, bitsize):
     else:
         valid_range = range(2**bitsize)
     qlt_testing.assert_consistent_classical_action(b, x=valid_range)
+
+
+def test_bitwise_not_str():
+    bloq = BitwiseNot(QUInt(5))
+    assert str(bloq) == "BitwiseNot(5)"

qualtran/bloqs/basic_gates/__init__.py

@@ -28,7 +28,7 @@
 from .identity import Identity
 from .on_each import OnEach
 from .power import Power
-from .rotation import CRz, CZPowGate, Rx, Ry, Rz, XPowGate, YPowGate, ZPowGate
+from .rotation import CRy, CRz, CZPowGate, Rx, Ry, Rz, XPowGate, YPowGate, ZPowGate
 from .s_gate import SGate
 from .su2_rotation import SU2RotationGate
 from .swap import CSwap, Swap, TwoBitCSwap, TwoBitSwap

qualtran/bloqs/basic_gates/global_phase.py

@@ -118,7 +118,7 @@ def _add_ctrled(
         return bloq, _add_ctrled
 
     def __str__(self) -> str:
-        return f'GPhase({self.coefficient})'
+        return f'GPhase({self.exponent})'
 
 
 @bloq_example

qualtran/bloqs/basic_gates/global_phase_test.py

@@ -77,3 +77,8 @@ def test_t_complexity():
 
 def test_global_phase(bloq_autotester):
     bloq_autotester(_global_phase)
+
+
+def test_global_phase_str():
+    bloq = GlobalPhase(exponent=0.5)
+    assert str(bloq) == "GPhase(0.5)"

qualtran/bloqs/basic_gates/on_each.py

@@ -96,4 +96,4 @@ def wire_symbol(self, reg: Optional[Register], idx: Tuple[int, ...] = tuple()) -
         return super().wire_symbol(reg, idx)
 
     def __str__(self):
-        return f'{self.gate}⨂{self.n}'
+        return f'{self.gate}(oneach={self.n})'

qualtran/bloqs/basic_gates/on_each_test.py

@@ -59,3 +59,8 @@ def test_call_graph():
     c1 = x_on_each.bloq_counts(generalizer=ignore_split_join)
     c2 = x_on_each.decompose_bloq().bloq_counts(generalizer=ignore_split_join)
     assert c1 == c2
+
+
+def test_on_each_str():
+    on_each = OnEach(10, XGate())
+    assert str(on_each) == "X(oneach=10)"