Working with Variables and Constants Programs Need a Way to Store the Data They Use Or Create So It Can Be Used Later in the Program’S Execution
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Semantic Navigation of Large Code Bases in Higher-Order, Dynamically Typed Languages
Semantic Navigation of Large Code Bases in Higher-Order, Dynamically Typed Languages S. Alexander Spoon and Olin Shivers College of Computing Georgia Institute of Technology Atlanta, GA 30032 Abstract— Chuck is a new code browser that allows navigation formed by deeper semantic connections between elements of of a code base along semantic structures, such as data-flow and the code, such as the data- and control-flow induced by the higher-order control-flow relationships. Employing the fast DDP dynamic semantics of the language. (In particular, note that type inferencer, it is effective on dynamically typed code bases an order of magnitude larger than the code bases supported by control flow in a higher-order functional or object-oriented previous browsers. Chuck supports the full Smalltalk language, language is no longer directly encoded in the syntax of the lan- and is now shipped as a standard component of the Squeak guage.) For example, semantic navigation allows programmers open-source Smalltalk system, where it routinely works with code to navigate from a new expression to the expressions that use bases exceeding 300,000 lines of code. Chuck’s implementation is objects created by that expression. It allows programmers to tuned for interactive use, and is transparently integrated with the Squeak system’s existing code-browsing tools. Thus, it provides navigate from a message-send expression to the narrow set of semantic navigation of a live code base that is still being edited methods that might respond to that specific invocation. These without requiring long pauses for reanalysis due to edits of the links, whose increased precision and tighter bounds help guide code. -
5. Data Types
IEEE FOR THE FUNCTIONAL VERIFICATION LANGUAGE e Std 1647-2011 5. Data types The e language has a number of predefined data types, including the integer and Boolean scalar types common to most programming languages. In addition, new scalar data types (enumerated types) that are appropriate for programming, modeling hardware, and interfacing with hardware simulators can be created. The e language also provides a powerful mechanism for defining OO hierarchical data structures (structs) and ordered collections of elements of the same type (lists). The following subclauses provide a basic explanation of e data types. 5.1 e data types Most e expressions have an explicit data type, as follows: — Scalar types — Scalar subtypes — Enumerated scalar types — Casting of enumerated types in comparisons — Struct types — Struct subtypes — Referencing fields in when constructs — List types — The set type — The string type — The real type — The external_pointer type — The “untyped” pseudo type Certain expressions, such as HDL objects, have no explicit data type. See 5.2 for information on how these expressions are handled. 5.1.1 Scalar types Scalar types in e are one of the following: numeric, Boolean, or enumerated. Table 17 shows the predefined numeric and Boolean types. Both signed and unsigned integers can be of any size and, thus, of any range. See 5.1.2 for information on how to specify the size and range of a scalar field or variable explicitly. See also Clause 4. 5.1.2 Scalar subtypes A scalar subtype can be named and created by using a scalar modifier to specify the range or bit width of a scalar type. -
1 Lesson 2 VARIABLES Aim Understanding How Computer
Lesson 2 VARIABLES Aim Understanding how computer programs store values, and how they are accessed and used in computer programs. WHAT ARE VARIABLES? When you input data (i.e. information) into a computer the data is stored in the computer’s memory. To visualise this, you might think of the computer’s memory as millions of little boxes, each holding a single value. Normally, each box is numbered starting at zero. As a computer uses binary numbers (made up of 0s and 1s), the boxes may be numbered something like this: 10100010, which is 162 in decimal. The actual number of boxes depends on the amount of memory in the specific computer. When data is put into the computer, the computer stores the data in the boxes that are part of the computer’s Random Access Memory (RAM), and the number of those boxes is referred to as the memory address. Obviously, for humans to refer to memory addresses by their binary index would be very difficult, so programming languages use a device called a variable. A variable is a word label that the programmer assigns to a piece of data, so they don’t need to worry about where it is stored in memory or how to tell the computer where to find it. Variables are simple memory boxes with names. You, the programmer, supply these names. For example, the following lines first declare a variable called myAge of data type Integer (it will store whole numbers), and then assigns the integer value 25 to myAge : Dim myAge As Integer myAge = 25 When you declare a variable, you must give it a name (and then compiler will claim some memory space and associate the name with the binary address), and specify the type of data that will be stored in that variable. -
Chapter 5: Substitutes for C Constructs
CHAPTER 5 Substitutes for C Constructs THE Java programming language shares many similarities with the C program- ming language, but several C constructs have been omitted. In most cases, it’s obvi- ous why a C construct was omitted and how to make do without it. This chapter suggests replacements for several omitted C constructs whose replacements are not so obvious. The common thread that connects the items in this chapter is that all of the omitted constructs are data-oriented rather than object-oriented. The Java pro- gramming language provides a powerful type system, and the suggested replace- ments take full advantage of that type system to deliver a higher quality abstraction than the C constructs they replace. Even if you choose to skip this chapter, it’s probably worth reading Item 21, which discusses the typesafe enum pattern, a replacement for C’s enum construct. This pattern is not widely known at the time of this writing, and it has several advan- tages over the methods currently in common use. Item 19: Replace structures with classes The C struct construct was omitted from the Java programming language because a class does everything a structure does and more. A structure merely groups multi- ple data fields into a single object; a class associates operations with the resulting object and allows the data fields to be hidden from users of the object. In other words, a class can encapsulate its data into an object that is accessed solely by its methods, allowing the implementor the freedom to change the representation over time (Item 12). -
On the Naming of Methods: a Survey of Professional Developers
On the Naming of Methods: A Survey of Professional Developers Reem S. Alsuhaibani Christian D. Newman Michael J. Decker Michael L. Collard Jonathan I. Maletic Computer Science Software Engineering Computer Science Computer Science Computer Science Kent State University Rochester Institute of Bowling Green State The University of Akron Kent State University Prince Sultan University Technology University Ohio, USA Ohio, USA Riyadh, Saudi Arabia New York, USA Ohio, USA [email protected] [email protected] [email protected] [email protected] [email protected] Abstract—This paper describes the results of a large (+1100 Here, we focus specifically on the names given to methods responses) survey of professional software developers concerning in object-oriented software systems. However, much of this also standards for naming source code methods. The various applies to (free) functions in non-object-oriented systems (or standards for source code method names are derived from and parts). We focus on methods for several reasons. First, we are supported in the software engineering literature. The goal of the interested in method naming in the context of automatic method survey is to determine if there is a general consensus among summarization and documentation. Furthermore, different developers that the standards are accepted and used in practice. programming language constructs have their own naming Additionally, the paper examines factors such as years of guidelines. That is, local variables are named differently than experience and programming language knowledge in the context methods, which are named differently than classes [10,11]. Of of survey responses. The survey results show that participants these, prior work has found that function names have the largest very much agree about the importance of various standards and how they apply to names and that years of experience and the number of unique name variants when analyzed at the level of programming language has almost no effect on their responses. -
Beaaqualogic Enterprise Security™®
BEAAquaLogic Enterprise Security™® Policy Managers Guide Version 2.6 Document Revised: April 2007 Contents 1. Introduction Document Scope and Audience. 1-1 Guide to this Document. 1-2 Related Documentation . 1-2 Contact Us! . 1-3 2. Security Policies Overview What is an AquaLogic Enterprise Security Policy? . 2-1 Closed-world Security Environment . 2-2 Policy Components . 2-3 Resources. 2-4 Virtual Resources . 2-6 Resource Attributes . 2-6 Privilege Groups. 2-6 Privileges . 2-6 Identities . 2-7 Identity Attributes. 2-8 Groups . 2-8 Users. 2-9 Roles. 2-10 Policies. 2-10 Role Mapping Policies . 2-10 Authorization Policies . 2-12 Delegation Policies. 2-13 Summary of Policy Differences . 2-14 Policy Managers Guide v Declarations. 2-14 Constants . 2-15 Enumerated Types . 2-15 Attributes . 2-15 Evaluation Functions . 2-15 3. Writing Policies Policy Implementation: Main Steps . 3-1 Access Decision Process . 3-4 Authentication Service. 3-4 Role Mapping Service . 3-4 Authorization Service . 3-5 Credential Mapping Service. 3-5 Authorization and Role Mapping Engine . 3-5 Using the Administration Console to Write Policies . 3-7 Administration Console Overview. 3-7 Defining Resources . 3-8 Virtual Resources . 3-11 Resource Attributes. 3-12 Privileges . 3-12 Privilege Groups . 3-13 Defining Identities . 3-14 Identity Attributes . 3-16 Groups. 3-16 Users . 3-17 Roles . 3-18 Writing Authorization and Role Mapping Policies . 3-19 Role Mapping Policies . 3-20 vi Policy Managers Guide Authorization Policies. 3-20 Role Mapping Policy Reports . 3-21 Authorization Policy Reports . 3-21 Defining Declarations. 3-22 Binding Policies . -
Jquery Fundamentals Rebecca Murphey [ Jquery Fundamentals Rebecca Murphey [ Copyright © 2010
jQuery Fundamentals Rebecca Murphey [http://www.rebeccamurphey.com] jQuery Fundamentals Rebecca Murphey [http://www.rebeccamurphey.com] Copyright © 2010 Licensed by Rebecca Murphey under the Creative Commons Attribution-Share Alike 3.0 United States license [http://creativecommons.org/licenses/ by-sa/3.0/us/]. You are free to copy, distribute, transmit, and remix this work, provided you attribute the work to Rebecca Murphey as the original author and reference the GitHub repository for the work [http://github.com/rmurphey/jqfundamentals]. If you alter, transform, or build upon this work, you may distribute the resulting work only under the same, similar or a compatible license. Any of the above conditions can be waived if you get permission from the copyright holder. For any reuse or distribution, you must make clear to others the license terms of this work. The best way to do this is with a link to the license [http://creativecommons.org/licenses/by-sa/3.0/us/]. Table of Contents 1. Welcome ....................................................................................................................... 1 Getting the Code ........................................................................................................ 1 Software ................................................................................................................... 1 Adding JavaScript to Your Page ................................................................................... 1 JavaScript Debugging ................................................................................................. -
Data Types Enumerated Types
CS 1044 Intro Programming in C++ Fall 2002 August 22, 2002 Data Types 9. Types 1 data type: a collection of values and the definition of one or more operations that can be performed on those values C++ includes a variety of built-in or base data types: short, int, long, float, double, char, etc. The values are ordered and atomic. C++ supports several mechanisms for aggregate data types: arrays, structures, classes. These allow complex combinations of other types as single entities. C++ also supports other mechanisms that allow programmers to define their own custom data types: enum types and typedefs. Computer Science Dept Va Tech August, 2002 Intro Programming in C++ ©1995-2002 Barnette ND & McQuain WD Enumerated Types 9. Types 2 An enumerated type is defined by giving a name for the type and then giving a list of labels, which are the only values that a variable of that type is allowed to have. Enumerated types allow the creation of specialized types that support the use of meaningful labels within a program. They promote code readability with very little overhead in memory or runtime cost. enum Month {JAN, FEB, MAR, APR, MAY, JUN, JUL, AUG, SEP, OCT, NOV, DEC}; enum Season {WINTER, SPRING, SUMMER, FALL}; enum Hemisphere {NORTH, SOUTH, EAST, WEST}; Month Mon; Season Period; Hemisphere Region; ... if (Mon == JAN && Region == NORTH) Period = WINTER; An enumerated type is allowed to have up to 256 values and a variable of an enumerated type will occupy one byte of memory. It is an error for the same label to be listed as a value for two different enumerated types. -
Object-Oriented Enumerated Type Facility
Europäisches Patentamt *EP001400895A2* (19) European Patent Office Office européen des brevets (11) EP 1 400 895 A2 (12) EUROPEAN PATENT APPLICATION (43) Date of publication: (51) Int Cl.7: G06F 9/44 24.03.2004 Bulletin 2004/13 (21) Application number: 03255511.2 (22) Date of filing: 03.09.2003 (84) Designated Contracting States: (72) Inventors: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR • Bloch, Joshua J. HU IE IT LI LU MC NL PT RO SE SI SK TR San José, CA 95129 (US) Designated Extension States: • Gafter, Neal M. AL LT LV MK San José, CA 95129 (US) (30) Priority: 09.09.2002 US 237941 (74) Representative: Davies, Simon Robert D Young & Co, (71) Applicant: Sun Microsystems, Inc. 21 New Fetter Lane Santa Clara, California 95054 (US) London, EC4A 1DA (GB) (54) Object-oriented enumerated type facility (57) A system and method are provided that facili- tate use of an object-oriented enumerated type within a computer program. During operation, the system re- ceives source code for the computer program. The source code contains a declaration for an enumerated type. This declaration specifies a fixed number of enu- meration constants that comprise the enumerated type. Next, the system defines the enumerated type using a class defined within an object-oriented programming language. The class includes a constant for each enu- meration constant specified in the declaration. If the declaration additionally contains one or more method declarations, these methods are present on the defined class. EP 1 400 895 A2 Printed by Jouve, 75001 PARIS (FR) EP 1 400 895 A2 Description Field of the Invention 5 [0001] The present invention relates to computer systems and to programming languages, and more specifically, to a method and an apparatus for facilitating the use of an object-oriented enumerated type within a programming lan- guage. -
Enumerated Types
Enumerated Types CSE160, Computer Science A: Honors Stony Brook University http://www.cs.stonybrook.edu/~cse160 1 Enumerated Types An enumerated type defines a list of enumerated values Each value is an identifier enum Day{SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY}; enum TrafficLight { RED, GREEN, YELLOW } A value of an enumerated type is like a constant and so, by convention, is spelled with all uppercase letters Also, by convention, an enumerated type is named like a class with first letter of each word capitalized Once a type is defined, you can declare a variable of that type: Day day; TrafficLight t; The variable day can hold one of the values defined in the enumerated type Day or null, but nothing else 2 (c) Pearson Education, Inc. & Paul Fodor (CS Stony Brook) Enumerated Types The enumerated values can be accessed using the syntax EnumeratedTypeName.valueName For example, the following statement assigns enumerated value Monday to variable day: Day day = Day.MONDAY; Using enumerated values (e.g., Day.MONDAY) rather than literal integer values (e.g., 0, 1, 2, 3, and so on) can make program easier to read and maintain An enumerated type is treated as a special class, so an enumerated type variable is therefore a reference variable An enumerated type is a subtype of the Object class (inherits all the methods in the Object class) and the Comparable interface (has the compareTo method in the Comparable interface) 3 (c) Pearson Education, Inc. & Paul Fodor (CS Stony Brook) Enumerated Types The following methods are defined for any enumerated object: public String name(); Returns a name of the value for the object (e.g. -
Function Declaration Vs Function Definition Javascript
Function Declaration Vs Function Definition Javascript Haemolytic and Cenozoic Oliver harmonise so schematically that Mylo democratising his pipestones. Morly glad-hands her mess indecently, valerianaceous and leaden. Awed Son still partialised: meticulous and rakehell Maynord lip quite apogamously but brooms her fragments suicidally. For earth, you register forward grasp a function or class however often do want, but you hold only half have one definition for it. And definition apply only declared inside the declarations load before everything is vs function declarations are like statements, and that concerns me a lookup to. Use inline comments sparingly. You well always dark the assignments that destructuring would generate yourself. There are leaving different ways that function expressions become more gas than function declarations. Wrapped lines are not indented. There can javascript function definition contains styles that we can write less work around docker is vs expression vs declarations are some different. Ecma RF patent policy. Function Definition, on than other hand, refers to the actual function that specifies the function name, return types and parameters with the function body. Made a banana cake! Functions that create values are easier to man in new ways than functions that directly perform side effects. Introduction to the old function simply want name may want the javascript function declaration vs definition. In javascript ad click help request that sort of declaring global is definitely a constant variable called a duplicate variable? Being declared inside multiple functions vs declaration declares that specifies how to declare it appears in. Read to Stay Baffled. But simply calling functions vs definition indicates the javascript function definitions: there is definitely on a react. -
Software II: Principles of Programming Languages
Software II: Principles of Programming Languages Lecture 6 – Data Types Some Basic Definitions • A data type defines a collection of data objects and a set of predefined operations on those objects • A descriptor is the collection of the attributes of a variable • An object represents an instance of a user- defined (abstract data) type • One design issue for all data types: What operations are defined and how are they specified? Primitive Data Types • Almost all programming languages provide a set of primitive data types • Primitive data types: Those not defined in terms of other data types • Some primitive data types are merely reflections of the hardware • Others require only a little non-hardware support for their implementation The Integer Data Type • Almost always an exact reflection of the hardware so the mapping is trivial • There may be as many as eight different integer types in a language • Java’s signed integer sizes: byte , short , int , long The Floating Point Data Type • Model real numbers, but only as approximations • Languages for scientific use support at least two floating-point types (e.g., float and double ; sometimes more • Usually exactly like the hardware, but not always • IEEE Floating-Point Standard 754 Complex Data Type • Some languages support a complex type, e.g., C99, Fortran, and Python • Each value consists of two floats, the real part and the imaginary part • Literal form real component – (in Fortran: (7, 3) imaginary – (in Python): (7 + 3j) component The Decimal Data Type • For business applications (money)