def semanticPredicateExpr(self):
"""
Find and generate code for a Python expression terminated by a
close-paren, whose return value determines the success of the pattern
it's in.
"""
expr = t.Action(self.pythonExpr(')')[0][0])
self.exactly(')')
return t.Predicate(expr)
def test_pred(self):
"""
Test code generation for predicate expressions.
"""
x = t.Predicate(t.Exactly("x"))
self.assertEqual(
writePython(x, ""),
dd("""
def _G_pred_1():
_G_exactly_2, lastError = self.exactly('x')
self.considerError(lastError, None)
return (_G_exactly_2, self.currentError)
_G_pred_3, lastError = self.pred(_G_pred_1)
self.considerError(lastError, None)
_G_pred_3
"""))
def test_pred(self):
x = t.Predicate(t.Action("doStuff()"))
self.assertEqual(
writeBytecode(x),
[t.Python('doStuff()'), t.Predicate()])
def generate_Predicate(self, out, expr, debugname=None):
self._generateNode(out, expr)
out.emit(t.Predicate())