CSE 431S Type Checking. Washington University Spring 2013
|
|
- Osborn Ward
- 5 years ago
- Views:
Transcription
1 CSE 431S Type Checking Washington University Spring 2013
2 Type Checking When are types checked? Statically at compile time Compiler does type checking during compilation Ideally eliminate runtime checks Dynamically at runtime Compiler generates code to do type checking at runtime JavaScript vs. Java Java still does a large amount of runtime type checking We ll focus on static typing for basic types
3 Types of Types Primitive types int, char, float, double, long, boolean Compound types array, struct, union, tuple, pointer? Object types OO language types Functions
4 What has a type? Variables (e.g. int x ) Functions Expressions (e.g. x + y ) + int float char int int float? float float float? char???
5 Compare + int float char int int float? float float float? char??? = int float char int int int int float float float float char char char char
6 Checking Expression Types z = x+y What is the type of x+y?
7 Checking Expression Types What if the variables are declared as: int x = 2; short y = 3; Is this allowed? What is the result (type and value)? What does the compiler need to do?
8 Expression Types For every operator we need to know allowed types of operands resulting type implicit coercion changes the representation, not the data short to long implicit conversion may change the data int to float explicit cast may lose information float to int, int to short
9 Which nodes have types? = x + y 3.14
10 A Visit from the Type Checking Visitor Depth first visit of nodes, perhaps using recursion: // pre-work foreach (child in childnodes) { child.accept(this); } // post-work
11 Type Checking Visitor 1 = 10 2 x y Pre-visit Post-visit
12 Type Checking Visit Why do work in post-visit? need to know types of children to validate types don t know types of children until they have been type checked
13 What are the types? =? x int +? y int 3.14 float
14 Determining Types make sure type is allowed (int + float) assign the resultant type to the operator (float) generate any necessary coercion(s) or conversion(s) most hardware has (int + int) and (float + float) but not (int + float)
15 Adding Coercion =? x int + float int 2 float float 3.14 float y int
16 But wait! Can you assign a float to an int? Most languages do not allow it How do we tell the compiler to cast? x = (int)(y+3.14) Most compilers won t automatically add float to int conversions compiler will throw a type error Does the assignment node get a type? s = t = 5
17 Explicit Casting = int x int float 2 int int + float int 2 float float 3.14 float y int
18 Visitor public class TypeChecker extends Visitor { public void visit(plusnode node) { visitchildren(node); node.type = getresultanttype(lhs, rhs); Node lc = getcoercionnode(lhs, node); if (lc!= null) node.insertleftchild(lc); Node rc = getcoercionnode(rhs, node); if (rc!= null) node.insertrightchild(rc); } }
19 Resultant Type How would you implement getresultanttype( )?
20 Implementation Every built in operation needs a visit method Other places have type requirements if, for, and while require boolean in Java
21 What is a struct? Are these equivalent? struct s1 { int x; }; struct s2 { int y; }; Compound Types
22 Function Call Type Checking A function can be viewed as a conversion of its parameter types to its return type short foo(int x, float y); A compiler should check parameters are of the correct type (or coercing if necessary) The resultant type of the function node is the return type At function call, assume that the returned value is the correct type Check the returned value when checking function body
23 Object Types
24 Object Types
25 Object Types
26 Object Type Checking Type hierarchy Java has Object as root All other class types are descendants of Object An object type is comprised of a parent class and any interfaces it implements Need to check assignment (that object type assigned to object variable is compatible (e.g. subtype)) lhs has to be equal or parent type of rhs otherwise, explicit downcast is required function or method call is legal for a type could be in a parent hierarchy or interface function overloading
Static Semantics. Winter /3/ Hal Perkins & UW CSE I-1
CSE 401 Compilers Static Semantics Hal Perkins Winter 2009 2/3/2009 2002-09 Hal Perkins & UW CSE I-1 Agenda Static semantics Types Symbol tables General ideas for now; details later for MiniJava project
More informationData Types. Every program uses data, either explicitly or implicitly to arrive at a result.
Every program uses data, either explicitly or implicitly to arrive at a result. Data in a program is collected into data structures, and is manipulated by algorithms. Algorithms + Data Structures = Programs
More informationC++ Important Questions with Answers
1. Name the operators that cannot be overloaded. sizeof,.,.*,.->, ::,? 2. What is inheritance? Inheritance is property such that a parent (or super) class passes the characteristics of itself to children
More informationType Analysis. Type Checking vs. Type Inference
Type Analysis Is an operator applied to an incompatible operand? Type checking: Static: Check for type compatibility at compile time Dynamic: Check for type compatibility at run time Type analysis phase
More informationCompiler Passes. Semantic Analysis. Semantic Analysis/Checking. Symbol Tables. An Example
Semantic Analysis Having figured out the program s structure, now figure out what it means Compiler Passes Analysis of input program (front-end) character stream Lexical Analysis token stream Syntactic
More informationMidterm CSE 131B Spring 2005
Signature Login Name _ Name Student ID Midterm CSE 131B Spring 2005 Page 1 Page 2 Page 3 Page 4 Page 5 (20 points) (18 points) (22 points) (20 points) (20 points) Subtotal Page 6 Extra Credit (100 points)
More informationIntroduction to Programming Using Java (98-388)
Introduction to Programming Using Java (98-388) Understand Java fundamentals Describe the use of main in a Java application Signature of main, why it is static; how to consume an instance of your own class;
More informationType Conversion. and. Statements
and Statements Type conversion changing a value from one type to another Void Integral Floating Point Derived Boolean Character Integer Real Imaginary Complex no fractional part fractional part 2 tj Suppose
More informationSemantic Analysis. How to Ensure Type-Safety. What Are Types? Static vs. Dynamic Typing. Type Checking. Last time: CS412/CS413
CS412/CS413 Introduction to Compilers Tim Teitelbaum Lecture 13: Types and Type-Checking 19 Feb 07 Semantic Analysis Last time: Semantic errors related to scopes Symbol tables Name resolution This lecture:
More informationCSC Java Programming, Fall Java Data Types and Control Constructs
CSC 243 - Java Programming, Fall 2016 Java Data Types and Control Constructs Java Types In general, a type is collection of possible values Main categories of Java types: Primitive/built-in Object/Reference
More informationJava Object Oriented Design. CSC207 Fall 2014
Java Object Oriented Design CSC207 Fall 2014 Design Problem Design an application where the user can draw different shapes Lines Circles Rectangles Just high level design, don t write any detailed code
More informationOutline. Java Models for variables Types and type checking, type safety Interpretation vs. compilation. Reasoning about code. CSCI 2600 Spring
Java Outline Java Models for variables Types and type checking, type safety Interpretation vs. compilation Reasoning about code CSCI 2600 Spring 2017 2 Java Java is a successor to a number of languages,
More informationData Types (cont.) Administrative Issues. Academic Dishonesty. How do we detect plagiarism? Strongly Typed Languages. Type System
CSE 3302 Programming Languages Data Types (cont.) Chengkai Li Fall 2007 1 Administrative Issues Midterm Exam (in class) Tuesday, Oct. 16 th Schedule Change HW1 HW1 part1 & HW1 part2 Due at the same time,
More informationNote 3. Types. Yunheung Paek. Associate Professor Software Optimizations and Restructuring Lab. Seoul National University
Note 3 Types Yunheung Paek Associate Professor Software Optimizations and Restructuring Lab. Seoul National University Topics Definition of a type Kinds of types Issues on types Type checking Type conversion
More informationLecture 7: Type Systems and Symbol Tables. CS 540 George Mason University
Lecture 7: Type Systems and Symbol Tables CS 540 George Mason University Static Analysis Compilers examine code to find semantic problems. Easy: undeclared variables, tag matching Difficult: preventing
More informationLecture #23: Conversion and Type Inference
Lecture #23: Conversion and Type Inference Administrivia. Due date for Project #2 moved to midnight tonight. Midterm mean 20, median 21 (my expectation: 17.5). Last modified: Fri Oct 20 10:46:40 2006 CS164:
More informationConversion vs. Subtyping. Lecture #23: Conversion and Type Inference. Integer Conversions. Conversions: Implicit vs. Explicit. Object x = "Hello";
Lecture #23: Conversion and Type Inference Administrivia. Due date for Project #2 moved to midnight tonight. Midterm mean 20, median 21 (my expectation: 17.5). In Java, this is legal: Object x = "Hello";
More informationTypes. What is a type?
Types What is a type? Type checking Type conversion Aggregates: strings, arrays, structures Enumeration types Subtypes Types, CS314 Fall 01 BGRyder 1 What is a type? A set of values and the valid operations
More informationCSC207H: Software Design. Java + OOP. CSC207 Winter 2018
Java + OOP CSC207 Winter 2018 1 Why OOP? Modularity: code can be written and maintained separately, and easily passed around the system Information-hiding: internal representation hidden from the outside
More informationCS 430 Spring Mike Lam, Professor. Data Types and Type Checking
CS 430 Spring 2015 Mike Lam, Professor Data Types and Type Checking Type Systems Type system Rules about valid types, type compatibility, and how data values can be used Benefits of a robust type system
More information5. Syntax-Directed Definitions & Type Analysis
5. Syntax-Directed Definitions & Type Analysis Eva Rose Kristoffer Rose NYU Courant Institute Compiler Construction (CSCI-GA.2130-001) http://cs.nyu.edu/courses/spring15/csci-ga.2130-001/lecture-5.pdf
More informationPrimitive Types. Four integer types: Two floating-point types: One character type: One boolean type: byte short int (most common) long
Primitive Types Four integer types: byte short int (most common) long Two floating-point types: float double (most common) One character type: char One boolean type: boolean 1 2 Primitive Types, cont.
More informationFundamentals of Programming Languages
Fundamentals of Programming Languages 1. DEFINITIONS... 2 2. BUILT-IN TYPES AND PRIMITIVE TYPES... 3 TYPE COMPATIBILITY... 9 GENERIC TYPES... 14 MONOMORPHIC VERSUS POLYMORPHIC... 16 TYPE IMPLEMENTATION
More informationCSE 12 Abstract Syntax Trees
CSE 12 Abstract Syntax Trees Compilers and Interpreters Parse Trees and Abstract Syntax Trees (AST's) Creating and Evaluating AST's The Table ADT and Symbol Tables 16 Using Algorithms and Data Structures
More informationCSE 431S Final Review. Washington University Spring 2013
CSE 431S Final Review Washington University Spring 2013 What You Should Know The six stages of a compiler and what each stage does. The input to and output of each compilation stage (especially the back-end).
More informationCSE P 501 Compilers. Static Semantics Hal Perkins Winter /22/ Hal Perkins & UW CSE I-1
CSE P 501 Compilers Static Semantics Hal Perkins Winter 2008 1/22/2008 2002-08 Hal Perkins & UW CSE I-1 Agenda Static semantics Types Attribute grammars Representing types Symbol tables Note: this covers
More informationSemantic Processing. Semantic Errors. Semantics - Part 1. Semantics - Part 1
Semantic Processing The Lexer and Parser Found lexical and syntax errors Built Abstract Syntax Tree Now!Find semantic errors.!build information about the program. Later!Generate IR Code!Optimize IR Code!Generate
More informationNon-numeric types, boolean types, arithmetic. operators. Comp Sci 1570 Introduction to C++ Non-numeric types. const. Reserved words.
, ean, arithmetic s s on acters Comp Sci 1570 Introduction to C++ Outline s s on acters 1 2 3 4 s s on acters Outline s s on acters 1 2 3 4 s s on acters ASCII s s on acters ASCII s s on acters Type: acter
More informationINDEX. A SIMPLE JAVA PROGRAM Class Declaration The Main Line. The Line Contains Three Keywords The Output Line
A SIMPLE JAVA PROGRAM Class Declaration The Main Line INDEX The Line Contains Three Keywords The Output Line COMMENTS Single Line Comment Multiline Comment Documentation Comment TYPE CASTING Implicit Type
More informationIntroduction & Java Review. EE 564 Lecture 1
Introduction & Java Review EE 564 Lecture 1 Course Overview Personnel introduction Course plan: theory: OO design 1 month practice 1: eclipse ~1.5 months practice 2: Java EE ~1.5 months Plan to devote
More informationTopic 9: Type Checking
Recommended Exercises and Readings Topic 9: Type Checking From Haskell: The craft of functional programming (3 rd Ed.) Exercises: 13.17, 13.18, 13.19, 13.20, 13.21, 13.22 Readings: Chapter 13.5, 13.6 and
More informationTopic 9: Type Checking
Topic 9: Type Checking 1 Recommended Exercises and Readings From Haskell: The craft of functional programming (3 rd Ed.) Exercises: 13.17, 13.18, 13.19, 13.20, 13.21, 13.22 Readings: Chapter 13.5, 13.6
More informationLecture Overview. [Scott, chapter 7] [Sebesta, chapter 6]
1 Lecture Overview Types 1. Type systems 2. How to think about types 3. The classification of types 4. Type equivalence structural equivalence name equivalence 5. Type compatibility 6. Type inference [Scott,
More informationChapter 2: Using Data
Chapter 2: Using Data TRUE/FALSE 1. A variable can hold more than one value at a time. F PTS: 1 REF: 52 2. The legal integer values are -2 31 through 2 31-1. These are the highest and lowest values that
More informationG Programming Languages Spring 2010 Lecture 6. Robert Grimm, New York University
G22.2110-001 Programming Languages Spring 2010 Lecture 6 Robert Grimm, New York University 1 Review Last week Function Languages Lambda Calculus SCHEME review 2 Outline Promises, promises, promises Types,
More informationTypes. Type checking. Why Do We Need Type Systems? Types and Operations. What is a type? Consensus
Types Type checking What is a type? The notion varies from language to language Consensus A set of values A set of operations on those values Classes are one instantiation of the modern notion of type
More informationConversions and Overloading : Overloading
Conversions and Overloading : First. Java allows certain implicit conversations of a value of one type to a value of another type. Implicit conversations involve only the primitive types. For example,
More informationCSE 374 Programming Concepts & Tools. Hal Perkins Spring 2010
CSE 374 Programming Concepts & Tools Hal Perkins Spring 2010 Lecture 12 C: structs, t linked lists, and casts Where we are We ve seen most of the basic stuff about C, but we still need to look at structs
More informationHANDLING NONLOCAL REFERENCES
SYMBOL TABLE A symbol table is a data structure kept by a translator that allows it to keep track of each declared name and its binding. Assume for now that each name is unique within its local scope.
More informationCS558 Programming Languages
CS558 Programming Languages Winter 2017 Lecture 7b Andrew Tolmach Portland State University 1994-2017 Values and Types We divide the universe of values according to types A type is a set of values and
More informationCompilers CS S-05 Semantic Analysis
Compilers CS414-2003S-05 Semantic Analysis David Galles Department of Computer Science University of San Francisco 05-0: Syntax Errors/Semantic Errors A program has syntax errors if it cannot be generated
More informationCSE P 501 Compilers. Static Semantics Hal Perkins Spring UW CSE P 501 Spring 2018 I-1
CSE P 501 Compilers Static Semantics Hal Perkins Spring 2018 UW CSE P 501 Spring 2018 I-1 Administrivia Parser + AST + print visitors due Mon. 11 pm How s it going? scanner-final and parser-final tags
More information1 Shyam sir JAVA Notes
1 Shyam sir JAVA Notes 1. What is the most important feature of Java? Java is a platform independent language. 2. What do you mean by platform independence? Platform independence means that we can write
More informationCS558 Programming Languages
CS558 Programming Languages Fall 2016 Lecture 7a Andrew Tolmach Portland State University 1994-2016 Values and Types We divide the universe of values according to types A type is a set of values and a
More informationCPSC 3740 Programming Languages University of Lethbridge. Data Types
Data Types A data type defines a collection of data values and a set of predefined operations on those values Some languages allow user to define additional types Useful for error detection through type
More informationName :. Roll No. :... Invigilator s Signature : INTRODUCTION TO PROGRAMMING. Time Allotted : 3 Hours Full Marks : 70
Name :. Roll No. :..... Invigilator s Signature :.. 2011 INTRODUCTION TO PROGRAMMING Time Allotted : 3 Hours Full Marks : 70 The figures in the margin indicate full marks. Candidates are required to give
More informationObject typing and subtypes
CS 242 2012 Object typing and subtypes Reading Chapter 10, section 10.2.3 Chapter 11, sections 11.3.2 and 11.7 Chapter 12, section 12.4 Chapter 13, section 13.3 Subtyping and Inheritance Interface The
More informationCSE 452: Programming Languages. Outline of Today s Lecture. Expressions. Expressions and Control Flow
CSE 452: Programming Languages Expressions and Control Flow Outline of Today s Lecture Expressions and Assignment Statements Arithmetic Expressions Overloaded Operators Type Conversions Relational and
More information22c:111 Programming Language Concepts. Fall Types I
22c:111 Programming Language Concepts Fall 2008 Types I Copyright 2007-08, The McGraw-Hill Company and Cesare Tinelli. These notes were originally developed by Allen Tucker, Robert Noonan and modified
More informationOperators and Expressions
Operators and Expressions Conversions. Widening and Narrowing Primitive Conversions Widening and Narrowing Reference Conversions Conversions up the type hierarchy are called widening reference conversions
More informationCMPSCI 187: Programming With Data Structures. Lecture #28: Binary Search Trees 21 November 2011
CMPSCI 187: Programming With Data Structures Lecture #28: Binary Search Trees 21 November 2011 Binary Search Trees The Idea of a Binary Search Tree The BinarySearchTreeADT Interface The LinkedBinarySearchTree
More informationCSE1720. General Info Continuation of Chapter 9 Read Chapter 10 for next week. Second level Third level Fourth level Fifth level
CSE1720 Click to edit Master Week text 08, styles Lecture 13 Second level Third level Fourth level Fifth level Winter 2014! Thursday, Feb 27, 2014 1 General Info Continuation of Chapter 9 Read Chapter
More informationChapter 7. Expressions and Assignment Statements
Chapter 7 Expressions and Assignment Statements Chapter 7 Topics Introduction Arithmetic Expressions Overloaded Operators Type Conversions Relational and Boolean Expressions Short-Circuit Evaluation Assignment
More informationInheritance & Polymorphism. Object-Oriented Programming Spring 2015
Inheritance & Polymorphism Object-Oriented Programming 236703 Spring 2015 1 1 Abstractions Reminder A class is an abstraction over objects A class hierarchy is an abstraction over classes Similar parts
More informationIntermediate Code Generation
Intermediate Code Generation In the analysis-synthesis model of a compiler, the front end analyzes a source program and creates an intermediate representation, from which the back end generates target
More informationArgument Passing All primitive data types (int etc.) are passed by value and all reference types (arrays, strings, objects) are used through refs.
Local Variable Initialization Unlike instance vars, local vars must be initialized before they can be used. Eg. void mymethod() { int foo = 42; int bar; bar = bar + 1; //compile error bar = 99; bar = bar
More informationExpressions & Assignment Statements
Expressions & Assignment Statements 1 Topics Introduction Arithmetic Expressions Overloaded Operators Type Conversions Relational and Boolean Expressions Short-Circuit Evaluation Assignment Statements
More informationThe Compiler So Far. CSC 4181 Compiler Construction. Semantic Analysis. Beyond Syntax. Goals of a Semantic Analyzer.
The Compiler So Far CSC 4181 Compiler Construction Scanner - Lexical analysis Detects inputs with illegal tokens e.g.: main 5 (); Parser - Syntactic analysis Detects inputs with ill-formed parse trees
More informationCSE450. Translation of Programming Languages. Lecture 11: Semantic Analysis: Types & Type Checking
CSE450 Translation of Programming Languages Lecture 11: Semantic Analysis: Types & Type Checking Structure Project 1 - of a Project 2 - Compiler Today! Project 3 - Source Language Lexical Analyzer Syntax
More informationCS61B Lecture #8: Object-Oriented Mechanisms
CS61B Lecture #8: Object-Oriented Mechanisms Public Service Announcement: CalSol, the UC Berkeley solar car team, is looking for new members. Preferably in MechE and EECS, but all welcome. See their web
More informationExpressions and Assignment
Expressions and Assignment COS 301: Programming Languages Outline Other assignment mechanisms Introduction Expressions: fundamental means of specifying computations Imperative languages: usually RHS of
More informationJava Inheritance. Written by John Bell for CS 342, Spring Based on chapter 6 of Learning Java by Niemeyer & Leuck, and other sources.
Java Inheritance Written by John Bell for CS 342, Spring 2018 Based on chapter 6 of Learning Java by Niemeyer & Leuck, and other sources. Review Which of the following is true? A. Java classes may either
More informationType Bindings. Static Type Binding
Type Bindings Two key issues in binding (or associating) a type to an identifier: How is type binding specified? When does the type binding take place? N. Meng, S. Arthur 1 Static Type Binding An explicit
More informationType Checking and Type Inference
Type Checking and Type Inference Principles of Programming Languages CSE 307 1 Types in Programming Languages 2 Static Type Checking 3 Polymorphic Type Inference Version: 1.8 17:20:56 2014/08/25 Compiled
More informationType Checking. Error Checking
Type Checking Error Checking Dynamic checking takes place while program is running Static checking takes place during compilation Type checks Flow-of-control checks Uniqueness checks Name-related checks
More informationData types. Definitions Aggregate constructors User-defined type definitions Types and storage Types and subtypes Type systems and type checking
Data types Definitions Aggregate constructors User-defined type definitions Types and storage Types and subtypes Type systems and type checking Ghezzi&Jazayeri: Ch 3 1 Data types Definition: a set of values
More informationtype conversion polymorphism (intro only) Class class
COMP 250 Lecture 33 type conversion polymorphism (intro only) Class class Nov. 24, 2017 1 Primitive Type Conversion double float long int short char byte boolean non-integers integers In COMP 273, you
More informationContents. I. Classes, Superclasses, and Subclasses. Topic 04 - Inheritance
Contents Topic 04 - Inheritance I. Classes, Superclasses, and Subclasses - Inheritance Hierarchies Controlling Access to Members (public, no modifier, private, protected) Calling constructors of superclass
More information3.Constructors and Destructors. Develop cpp program to implement constructor and destructor.
3.Constructors and Destructors Develop cpp program to implement constructor and destructor. Constructors A constructor is a special member function whose task is to initialize the objects of its class.
More informationQUIZ. 1. Explain the meaning of the angle brackets in the declaration of v below:
QUIZ 1. Explain the meaning of the angle brackets in the declaration of v below: This is a template, used for generic programming! QUIZ 2. Why is the vector class called a container? 3. Explain how the
More informationOrganization of Programming Languages CS320/520N. Lecture 06. Razvan C. Bunescu School of Electrical Engineering and Computer Science
Organization of Programming Languages CS320/520N Razvan C. Bunescu School of Electrical Engineering and Computer Science bunescu@ohio.edu Data Types A data type defines a collection of data objects and
More informationCompilers. Type checking. Yannis Smaragdakis, U. Athens (original slides by Sam
Compilers Type checking Yannis Smaragdakis, U. Athens (original slides by Sam Guyer@Tufts) Summary of parsing Parsing A solid foundation: context-free grammars A simple parser: LL(1) A more powerful parser:
More informationCSC207H: Software Design. Java + OOP. CSC207 Winter 2018
Java + OOP CSC207 Winter 2018 1 Why OOP? Modularity: code can be written and maintained separately, and easily passed around the system Information-hiding: internal representation hidden from the outside
More informationJava and C CSE 351 Spring
Java and C CSE 351 Spring 2018 https://xkcd.com/801/ Roadmap C: car *c = malloc(sizeof(car)); c->miles = 100; c->gals = 17; float mpg = get_mpg(c); free(c); Assembly language: Machine code: get_mpg: pushq
More informationEntry Point of Execution: the main Method. Elementary Programming. Compile Time vs. Run Time. Learning Outcomes
Entry Point of Execution: the main Method Elementary Programming EECS2030: Advanced Object Oriented Programming Fall 2017 CHEN-WEI WANG For now, all your programming exercises will be defined within the
More informationCharacter Stream : It provides a convenient means for handling input and output of characters.
Be Perfect, Do Perfect, Live Perfect 1 1. What is the meaning of public static void main(string args[])? public keyword is an access modifier which represents visibility, it means it is visible to all.
More informationExpressions and Casting
Expressions and Casting C# Programming Rob Miles Data Manipulation We know that programs use data storage (variables) to hold values and statements to process the data The statements are obeyed in sequence
More informationCS412/CS413. Introduction to Compilers Tim Teitelbaum. Lecture 17: Types and Type-Checking 25 Feb 08
CS412/CS413 Introduction to Compilers Tim Teitelbaum Lecture 17: Types and Type-Checking 25 Feb 08 CS 412/413 Spring 2008 Introduction to Compilers 1 What Are Types? Types describe the values possibly
More informationCSC 467 Lecture 13-14: Semantic Analysis
CSC 467 Lecture 13-14: Semantic Analysis Recall Parsing is to translate token stream to parse tree Today How to build trees: syntax direction translation How to add information to trees: semantic analysis
More informationChapter 7. Expressions and Assignment Statements (updated edition 11) ISBN
Chapter 7 Expressions and Assignment Statements (updated edition 11) ISBN 0-321-49362-1 Chapter 7 Topics Introduction Arithmetic Expressions Overloaded Operators Type Conversions Relational and Boolean
More informationTopics Covered Thus Far CMSC 330: Organization of Programming Languages
Topics Covered Thus Far CMSC 330: Organization of Programming Languages Names & Binding, Type Systems Programming languages Ruby Ocaml Lambda calculus Syntax specification Regular expressions Context free
More informationInheritance, Polymorphism and the Object Memory Model
Inheritance, Polymorphism and the Object Memory Model 1 how objects are stored in memory at runtime? compiler - operations such as access to a member of an object are compiled runtime - implementation
More informationWeek 7. Statically-typed OO languages: C++ Closer look at subtyping
C++ & Subtyping Week 7 Statically-typed OO languages: C++ Closer look at subtyping Why talk about C++? C++ is an OO extension of C Efficiency and flexibility from C OO program organization from Simula
More informationEL2310 Scientific Programming
Lecture 11: Structures and Memory (yaseminb@kth.se) Overview Overview Lecture 11: Structures and Memory Structures Continued Memory Allocation Lecture 11: Structures and Memory Structures Continued Memory
More informationExpressions and Assignment Statements
Expressions and Assignment Statements Introduction Expressions are the fundamental means of specifying computations in a programming language To understand expression evaluation, need to be familiar with
More informationTester vs. Controller. Elementary Programming. Learning Outcomes. Compile Time vs. Run Time
Tester vs. Controller Elementary Programming EECS1022: Programming for Mobile Computing Winter 2018 CHEN-WEI WANG For effective illustrations, code examples will mostly be written in the form of a tester
More informationType Checking. Chapter 6, Section 6.3, 6.5
Type Checking Chapter 6, Section 6.3, 6.5 Inside the Compiler: Front End Lexical analyzer (aka scanner) Converts ASCII or Unicode to a stream of tokens Syntax analyzer (aka parser) Creates a parse tree
More informationCS 112 Introduction to Computing II. Wayne Snyder Computer Science Department Boston University
CS 112 Introduction to Computing II Wayne Snyder Department Boston University Today: Java basics: Compilation vs Interpretation Program structure Statements Values Variables Types Operators and Expressions
More information1 Terminology. 2 Environments and Static Scoping. P. N. Hilfinger. Fall Static Analysis: Scope and Types
and Computer Sciences Computer Science Division CS 164 Fall 2006 P. N. Hilfinger Static Analysis: Scope and Types 1 Terminology Programs, in general, are simply collections of definitions of terms, which
More information9/7/17. Outline. Name, Scope and Binding. Names. Introduction. Names (continued) Names (continued) In Text: Chapter 5
Outline Name, Scope and Binding In Text: Chapter 5 Names Variable Binding Type bindings, type conversion Storage bindings and lifetime Scope Lifetime vs. Scope Referencing Environments N. Meng, S. Arthur
More informationChapter 2: Basic Elements of Java
Chapter 2: Basic Elements of Java TRUE/FALSE 1. The pair of characters // is used for single line comments. ANS: T PTS: 1 REF: 29 2. The == characters are a special symbol in Java. ANS: T PTS: 1 REF: 30
More informationElementary Programming
Elementary Programming EECS1022: Programming for Mobile Computing Winter 2018 CHEN-WEI WANG Learning Outcomes Learn ingredients of elementary programming: data types [numbers, characters, strings] literal
More informationJava: introduction to object-oriented features
Chair of Software Engineering Carlo A. Furia, Marco Piccioni, Bertrand Meyer Java: introduction to object-oriented features Chair of Software Engineering Carlo A. Furia, Marco Piccioni, Bertrand Meyer
More informationStrict Inheritance. Object-Oriented Programming Winter
Strict Inheritance Object-Oriented Programming 236703 Winter 2014-5 1 1 Abstractions Reminder A class is an abstraction over objects A class hierarchy is an abstraction over classes Similar parts of different
More informationChapter 7. Expressions and Assignment Statements ISBN
Chapter 7 Expressions and Assignment Statements ISBN 0-321-33025-0 Chapter 7 Topics Introduction Arithmetic Expressions Overloaded Operators Type Conversions Relational and Boolean Expressions Short-Circuit
More informationSpecial Topics: Programming Languages
Lecture #23 0 V22.0490.001 Special Topics: Programming Languages B. Mishra New York University. Lecture # 23 Lecture #23 1 Slide 1 Java: History Spring 1990 April 1991: Naughton, Gosling and Sheridan (
More informationMore On inheritance. What you can do in subclass regarding methods:
More On inheritance What you can do in subclass regarding methods: The inherited methods can be used directly as they are. You can write a new static method in the subclass that has the same signature
More informationEntry Point of Execution: the main Method. Elementary Programming. Learning Outcomes. Development Process
Entry Point of Execution: the main Method Elementary Programming EECS1021: Object Oriented Programming: from Sensors to Actuators Winter 2019 CHEN-WEI WANG For now, all your programming exercises will
More informationZheng-Liang Lu Java Programming 45 / 79
1 class Lecture2 { 2 3 "Elementray Programming" 4 5 } 6 7 / References 8 [1] Ch. 2 in YDL 9 [2] Ch. 2 and 3 in Sharan 10 [3] Ch. 2 in HS 11 / Zheng-Liang Lu Java Programming 45 / 79 Example Given a radius
More informationProject Compiler. CS031 TA Help Session November 28, 2011
Project Compiler CS031 TA Help Session November 28, 2011 Motivation Generally, it s easier to program in higher-level languages than in assembly. Our goal is to automate the conversion from a higher-level
More information