Python Distilled

355 Pages·2021·2.972 MB·English

by  David Beazley

Python Distilled
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Python Distilled
David M. Beazley
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ISBN-13:978-0-13-417327-6
ISBN-10:0-13-417327-9
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Contents
Preface xiii
1 Python Basics 1
1.1 RunningPython 1
1.2 PythonPrograms 2
1.3 Primitives,Variables,and
Expressions 3
1.4 ArithmeticOperators 5
1.5 ConditionalsandControlFlow 7
1.6 TextStrings 9
1.7 FileInputandOutput 12
1.8 Lists 13
1.9 Tuples 15
1.10 Sets 17
1.11 Dictionaries 18
1.12 IterationandLooping 21
1.13 Functions 22
1.14 Exceptions 24
1.15 ProgramTermination 26
1.16 ObjectsandClasses 26
1.17 Modules 30
1.18 ScriptWriting 32
1.19 Packages 33
1.20 StructuringanApplication 34
1.21 ManagingThird-PartyPackages 35
1.22 Python:ItFitsYourBrain 36
2 Operators, Expressions, and Data
Manipulation 37
2.1 Literals 37
2.2 ExpressionsandLocations 38
2.3 StandardOperators 39
2.4 In-PlaceAssignment 41
2.5 ObjectComparison 42
2.6 OrderedComparisonOperators 42
vi Contents
2.7 BooleanExpressionsandTruth
Values 43
2.8 ConditionalExpressions 44
2.9 OperationsInvolvingIterables 45
2.10 OperationsonSequences 47
2.11 OperationsonMutable
Sequences 49
2.12 OperationsonSets 50
2.13 OperationsonMappings 51
2.14 List,Set,andDictionary
Comprehensions 52
2.15 GeneratorExpressions 54
2.16 TheAttribute(.)Operator 56
2.17 TheFunctionCall()Operator 56
2.18 OrderofEvaluation 56
2.19 FinalWords:TheSecretLifeof
Data 58
3 Program Structure and Control
Flow 59
3.1 ProgramStructureand
Execution 59
3.2 ConditionalExecution 59
3.3 LoopsandIteration 60
3.4 Exceptions 64
3.4.1 TheException
Hierarchy 67
3.4.2 ExceptionsandControl
Flow 68
3.4.3 DefiningNew
Exceptions 69
3.4.4 ChainedExceptions 70
3.4.5 Exception
Tracebacks 73
3.4.6 ExceptionHandling
Advice 73
3.5 ContextManagersandthewith
Statement 75
3.6 Assertionsand__debug__ 77
3.7 FinalWords 78
Contents vii
4 Objects, Types, and Protocols 79
4.1 EssentialConcepts 79
4.2 ObjectIdentityandType 80
4.3 ReferenceCountingandGarbage
Collection 81
4.4 ReferencesandCopies 83
4.5 ObjectRepresentationandPrinting 84
4.6 First-ClassObjects 85
4.7 UsingNoneforOptionalorMissing
Data 87
4.8 ObjectProtocolsandData
Abstraction 87
4.9 ObjectProtocol 89
4.10 NumberProtocol 90
4.11 ComparisonProtocol 92
4.12 ConversionProtocols 94
4.13 ContainerProtocol 95
4.14 IterationProtocol 97
4.15 AttributeProtocol 98
4.16 FunctionProtocol 98
4.17 ContextManagerProtocol 99
4.18 FinalWords:OnBeingPythonic 99
5 Functions 101
5.1 FunctionDefinitions 101
5.2 DefaultArguments 101
5.3 VariadicArguments 102
5.4 KeywordArguments 103
5.5 VariadicKeywordArguments 104
5.6 FunctionsAcceptingAllInputs 104
5.7 Positional-OnlyArguments 105
5.8 Names,DocumentationStrings,andType
Hints 106
5.9 FunctionApplicationandParameter
Passing 107
5.10 ReturnValues 109
5.11 ErrorHandling 110
5.12 ScopingRules 111
5.13 Recursion 114
viii Contents
5.14 ThelambdaExpression 114
5.15 Higher-OrderFunctions 115
5.16 ArgumentPassinginCallback
Functions 118
5.17 ReturningResultsfrom
Callbacks 121
5.18 Decorators 124
5.19 Map,Filter,andReduce 127
5.20 FunctionIntrospection,Attributes,
andSignatures 129
5.21 EnvironmentInspection 131
5.22 DynamicCodeExecutionand
Creation 133
5.23 AsynchronousFunctionsand
await 135
5.24 FinalWords:ThoughtsonFunctions
andComposition 137
6 Generators 139
6.1 Generatorsandyield 139
6.2 RestartableGenerators 142
6.3 GeneratorDelegation 142
6.4 UsingGeneratorsinPractice 144
6.5 EnhancedGeneratorsandyield
Expressions 146
6.6 ApplicationsofEnhanced
Generators 148
6.7 GeneratorsandtheBridgeto
Awaiting 151
6.8 FinalWords:ABriefHistoryof
GeneratorsandLooking
Forward 152
7 Classes and Object-Oriented
Programming 153
7.1 Objects 153
7.2 TheclassStatement 154
7.3 Instances 155
7.4 AttributeAccess 156
7.5 ScopingRules 158
Contents ix
7.6 OperatorOverloadingandProtocols 159
7.7 Inheritance 160
7.8 AvoidingInheritanceviaComposition 163
7.9 AvoidingInheritanceviaFunctions 166
7.10 DynamicBindingandDuckTyping 167
7.11 TheDangerofInheritingfromBuilt-in
Types 167
7.12 ClassVariablesandMethods 169
7.13 StaticMethods 173
7.14 AWordaboutDesignPatterns 176
7.15 DataEncapsulationandPrivate
Attributes 176
7.16 TypeHinting 179
7.17 Properties 180
7.18 Types,Interfaces,andAbstractBase
Classes 183
7.19 MultipleInheritance,Interfaces,and
Mixins 187
7.20 Type-BasedDispatch 193
7.21 ClassDecorators 194
7.22 SupervisedInheritance 197
7.23 TheObjectLifeCycleandMemory
Management 199
7.24 WeakReferences 204
7.25 InternalObjectRepresentationand
AttributeBinding 206
7.26 Proxies,Wrappers,andDelegation 208
7.27 ReducingMemoryUsewith
__slots__ 210
7.28 Descriptors 211
7.29 ClassDefinitionProcess 215
7.30 DynamicClassCreation 216
7.31 Metaclasses 217
7.32 Built-inObjectsforInstancesand
Classes 222
7.33 FinalWords:KeepItSimple 223
8 Modules and Packages 225
8.1 ModulesandtheimportStatement 225