1# Copyright 2021, Kay Hayen, mailto:kay.hayen@gmail.com 2# 3# Part of "Nuitka", an optimizing Python compiler that is compatible and 4# integrates with CPython, but also works on its own. 5# 6# Licensed under the Apache License, Version 2.0 (the "License"); 7# you may not use this file except in compliance with the License. 8# You may obtain a copy of the License at 9# 10# http://www.apache.org/licenses/LICENSE-2.0 11# 12# Unless required by applicable law or agreed to in writing, software 13# distributed under the License is distributed on an "AS IS" BASIS, 14# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15# See the License for the specific language governing permissions and 16# limitations under the License. 17# 18""" Built-in iterator nodes. 19 20These play a role in for loops, and in unpacking. They can something be 21predicted to succeed or fail, in which case, code can become less complex. 22 23The length of things is an important optimization issue for these to be 24good. 25""" 26 27from nuitka.specs import BuiltinParameterSpecs 28 29from .ExpressionBases import ExpressionBuiltinSingleArgBase 30from .shapes.BuiltinTypeShapes import tshape_int_or_long 31 32 33class ExpressionBuiltinLen(ExpressionBuiltinSingleArgBase): 34 kind = "EXPRESSION_BUILTIN_LEN" 35 36 builtin_spec = BuiltinParameterSpecs.builtin_len_spec 37 38 def getIntegerValue(self): 39 value = self.subnode_value 40 41 if value.hasShapeSlotLen(): 42 return value.getIterationLength() 43 else: 44 return None 45 46 def computeExpression(self, trace_collection): 47 return self.subnode_value.computeExpressionLen( 48 len_node=self, trace_collection=trace_collection 49 ) 50 51 @staticmethod 52 def getTypeShape(): 53 # Length could be really big, using a long. 54 return tshape_int_or_long 55 56 def mayRaiseException(self, exception_type): 57 value = self.subnode_value 58 59 if value.mayRaiseException(exception_type): 60 return True 61 62 return not value.getTypeShape().hasShapeSlotLen() 63