CSC 461 Ch1

program counter

. Each instruction to be executed must be moved from memory to the processor. The address of the next instruction to be executed is maintained in a register called the

programming environment

A collection of tools used in software development

reliable

A program is said to be _______ if it performs to its specifications under all conditions.

Increased capacity to express ideas Improved BAckground for choosing appropriate languages Increased ability to learn new languages Better understanding of the significance of implementation Better use of languages that are already known Overall advancement of computing

Benefits of studying concepts of programming languages

Training programmers writing the program compiling programs executing programs language implementation system poor reliability maintaining programs

Costs of writing a program

compiled

Is compiled or interpreter faster?

Readability

One of the most important criteria for judging a programming language is the ease with which programs can be read and understood.

a single instruction can use either registers or memory cells as the operands.

The VAX instruction design is orthogonal in that

HTML

The World Wide Web is supported by an eclectic collection of languages, ranging from markup languages, such

overall simplicity

The _____________ of a programming language strongly affects its readability

Exception handling

The ability of a program to intercept run-time errors (as well as other unusual conditions detectable by the program), take corrective measures, and then continue is an obvious aid to reliability.

fetch-execute cycle

The execution of a machine code program on a von Neumann architecture computer occurs in a process called

Fortran

The first language for scientific applications was

Cobol

The first successful high- level language for business was

source language

The language that a compiler translates

linking and loading

The process of collecting system programs and linking them to user programs is called

von Neumann bottleneck

The speed of the connection between a computer's memory and its processor often determines the speed of the computer, because instructions often can be executed faster than they can be moved to the processor for execution.

load module or executable image

The user and system code together are sometimes called a

platform independence easier to debug and easier to get source code smaller in size automatic memory management

What are the advantages in implementing a language with a pure interpreter?

Data Abstraction Inheritance Dynamic Method Binding or Polymorphism

What are the three fundamental features of an object-oriented programming language?

Compiler Implementation Just In Time (JIT) or interpreted implementation The combination of both compiled and interpreted implementation

What are the three general methods of implementing a programming language?

Smalltalk

What language was the first to support the three fundamental features of object-oriented programming?

Lack of type checking can lead to unreliability of the code Inadequacy of control statements requiring extensive usage of goto statements

What two programming language deficiencies were discovered as a result of the research in software development in the 1970s?

Pure interpretation

With this approach, programs are interpreted by another program called an interpreter, with no translation whatsoever.

hybrid implementation systems

a compromise between compilers and pure interpreters; they translate high- level language programs to an intermediate language designed to allow easy interpretation

Simplicity Orthogonality Data Types Syntax Design

characteristics that affect Readability

Simplicity Orthogonality Data Types Syntax Design Support for abstraction Expressivity Type Checking Exception Handling Restricted aliasing

characteristics that affect Reliability

Simplicity Orthogonality Data Types Syntax Design Support for abstraction Expressivity

characteristics that affect Writability

is feature multiplicity

having more than one way to accomplish a particular operation

NetBeans

is a development environment that is primarily used for Java application development but also supports JavaScript, Ruby, and PHP.

total cost

is a function of many of its characteristics.

Writability

is a measure of how easily a language can be used to create programs for a chosen problem domain

preprocessor

is a program that processes a program just before the program is compiled

aliasing

is having two or more distinct names in a program that can be used to access the same memory cell.

Type checking

is simply testing for type errors in a given program, either by the compiler or during program execution.

Optimization

is the name given to the collection of techniques that compilers may use to decrease the size and/or increase the execution speed of the code they produce

Lisp

language used in artificial intelligence

New software development methodologies

led to new programming paradigms and by extension, new programming languages

linker

linking is accomplished by a systems program called a

Orthogonality

means that a relatively small set of primitive constructs can be combined in a relatively small number of ways to build the control and data structures of the language.

Expressivity

means that there are very powerful operators that allow a great deal of computation to be accomplished with a very small program. More commonly, it means that a language has relatively convenient, rather than cumbersome, ways of specifying computations.

von Neumann architecture

prevalent computer architecture

compiler implementation

programs can be translated into machine language, which can be executed directly on the computer

parse trees

represent the syntactic structure of the program.

Generality

the applicability to a wide range of applications

well-definedness

the completeness and precision of the language's official defining document

portability

the ease with which programs can be moved from one implementation to another

Errors in programs can go undetected when nearly any combination of primitives is legal. This can lead to code absurdities that cannot be discovered by the compiler.

too much orthogonality can be a detriment to writability.

operator overloading

which a single operator symbol has more than one meaning