PL/I Programming Concepts
29 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What was the initial motivation behind the development of Smalltalk?

  • To create a language focused on numerical computation.
  • To realize the concept of the Dynabook. (correct)
  • To provide a platform for advanced operating systems.
  • To develop a new version of the Xerox Alto.

    • In Smalltalk, how is computation typically carried out?

  • By manipulating data through direct memory access.
  • By executing predefined functions.
  • By using mathematical operations on variable values.
  • By sending messages to objects to invoke their methods. (correct)

    • What is the primary purpose of a class in Smalltalk?

  • To directly perform computations by executing code.
  • To manage the communication between different objects.
  • To serve as an abstract template for creating objects. (correct)
  • To define the operational methods used by objects.

    • What characteristic is NOT a fundamental part of Smalltalk programming?

    <p>Directly manipulating variables to perform calculations (C)</p> Signup and view all the answers

    What does the following line in a Smalltalk program signify: ourPen

    <p>An instance variable. (B)</p> Signup and view all the answers

    Which programming language was designed with the goal of being applicable across a broad range of areas?

    <p>PL/I (D)</p> Signup and view all the answers

    Which feature was NOT a first for a programming language, introduced by PL/I?

    <p>Dynamic memory allocation (B)</p> Signup and view all the answers

    What is the main purpose of the provided PL/I code?

    <p>To find the number of list values above the average (B)</p> Signup and view all the answers

    What does the PUT SKIP LIST statement do in the PL/I code?

    <p>It skips a line and prints a list of values. (B)</p> Signup and view all the answers

    What is a key characteristic shared by APL and SNOBOL?

    <p>They both have dynamic typing and storage allocation. (C)</p> Signup and view all the answers

    What distinguishes APL from many other programming languages?

    <p>Its large number of specialized operators. (A)</p> Signup and view all the answers

    For what is SNOBOL primarily designed?

    <p>Text processing with string pattern matching. (B)</p> Signup and view all the answers

    Which language incorporates features from Algol 60, Fortran IV, and COBOL?

    <p>PL/I (C)</p> Signup and view all the answers

    Which programming language introduced the 'class' construct?

    <p>SIMULA 67 (B)</p> Signup and view all the answers

    What was the primary design goal of the C programming language?

    <p>To implement the UNIX operating system. (A)</p> Signup and view all the answers

    In the provided C program, what is the purpose of the if ((listlen > 0) && (listlen < 100)) condition?

    <p>To ensure the input list length is within an acceptable range. (B)</p> Signup and view all the answers

    What is the value of j printed by the C program: for(int i=(j=1)*n; i; j=j*i--); printf("%d",j); if n is 3?

    <p>6 (C)</p> Signup and view all the answers

    What does the C code for(char *p=str, *q=str+strlen(str)-1; p < q ; p++,q--) achieve?

    <p>It reverses the string 'str' in place. (B)</p> Signup and view all the answers

    What is the purpose of scanf in the provided C code?

    <p>To receive the length of the list and the values from the user. (D)</p> Signup and view all the answers

    Which of these languages was NOT a direct ancestor of C?

    <p>SIMULA 67 (B)</p> Signup and view all the answers

    In the provided C program, what is the final value of result?

    <p>The count of numbers greater than the average. (A)</p> Signup and view all the answers

    In the given Ada code snippet for Ada_Ex, what is the purpose of the Result variable?

    <p>To count the number of elements in <code>Int_List</code> that are greater than the average. (C)</p> Signup and view all the answers

    What condition is checked before the loop in the Ada_Ex program?

    <p>If <code>Int_List</code> is not empty and <code>List_Len</code> is a non-negative integer. (B)</p> Signup and view all the answers

    In the PRODUCER_CONSUMER Ada program, what is the purpose of the BUFFER task?

    <p>To act as a shared data structure between the <code>PRODUCER</code> and <code>CONSUMER</code> tasks. (B)</p> Signup and view all the answers

    What is the role of the PRODUCER_DONE entry in the BUFFER task?

    <p>To indicate that the <code>PRODUCER</code> task has finished producing data for the <code>BUFFER</code>. (A)</p> Signup and view all the answers

    In the BUFFER task, how is the circular buffer implemented?

    <p>Using modulo (<code>rem</code>) operation on <code>BUFFER_REAR</code> and <code>BUFFER_FRONT</code> to wrap around array indices. (C)</p> Signup and view all the answers

    What action does the statement CONSUMER.NO_MORE_CARDS; perform in the BUFFER task?

    <p>It signals the <code>CONSUMER</code> that no more cards will be produced/made. (C)</p> Signup and view all the answers

    What would happen if the BUFFER_SIZE was significantly larger than the actual number of items the producer added to the buffer, without the PRODUCER_DONE signal?

    <p>The <code>CONSUMER</code> task could potentially read junk/garbage values if it tried to retrieve too many items once the producer had stopped and the <code>BUFFER</code> was empty. (B)</p> Signup and view all the answers

    In the given BUFFER task, what do the BUFFER_EMPTY and BUFFER_FULL boolean flags represent?

    <p><code>BUFFER_EMPTY</code> is true when the buffer is empty and ready to receive items, and <code>BUFFER_FULL</code> is true when buffer is full and no more items can be added. (A)</p> Signup and view all the answers

    Flashcards

    Smalltalk

    The first object-oriented programming language, developed in the late 1960s.

    Object-oriented programming

    A programming paradigm where data is represented as objects.

    Dynabook

    A conceptual portable computer idea proposed by Alan Kay.

    Smalltalk-80

    An improved version of Smalltalk developed in 1980, featuring a graphical user interface.

    Signup and view all the flashcards

    Class in Smalltalk

    A blueprint for creating objects and managing methods in Smalltalk.

    Signup and view all the flashcards

    PL/I

    A programming language developed by IBM in 1963 for various application areas, combining features from multiple languages.

    Signup and view all the flashcards

    Features of PL/I

    Includes features like concurrent subprograms, exception handling, efficient linkage, pointers, and array cross-sections.

    Signup and view all the flashcards

    Exception handling in PL/I

    PL/I introduced 23 different types of exceptions or run-time errors for improved error management.

    Signup and view all the flashcards

    Dynamic Typing

    A feature where variable types are determined at runtime, rather than compile time, allowing flexibility in coding.

    Signup and view all the flashcards

    APL

    A programming language designed at IBM in 1960 with powerful operators but difficult to maintain.

    Signup and view all the flashcards

    SNOBOL

    A programming language created for text processing in the early 1960s, particularly strong in string pattern matching.

    Signup and view all the flashcards

    Input/Output in PL/I

    PL/I provides sophisticated facilities for input/output operations, including data structures and report generation.

    Signup and view all the flashcards

    PL/I program structure

    Consists of procedures that declare variables, perform calculations, and handle conditions based on inputs.

    Signup and view all the flashcards

    SIMULA 67

    A programming language developed in 1967, extending Algol 60 to include coroutines and classes.

    Signup and view all the flashcards

    C Programming Language

    Developed at Bell Labs in 1972, C is designed for UNIX implementation and has ancestors like B and Algol 68.

    Signup and view all the flashcards

    Coroutines

    A programming construct that generalizes subroutines, allowing multiple entry points for suspending and resuming execution.

    Signup and view all the flashcards

    Class Construct

    A blueprint for creating objects in object-oriented programming, encapsulating data and functions.

    Signup and view all the flashcards

    ANSI C

    The first official standard for the C programming language, established in 1989, ensuring compatibility across compilers.

    Signup and view all the flashcards

    C Program Structure

    Typical C program consists of functions, with 'int main()' being the entry point.

    Signup and view all the flashcards

    Type Checking

    The process of verifying that a variable's data type is correct under the rules of the programming language.

    Signup and view all the flashcards

    Input Validation

    The process of ensuring that input data meets desired criteria before processing it.

    Signup and view all the flashcards

    List_Len loop

    A loop that counts how many numbers in a list exceed the average.

    Signup and view all the flashcards

    Buffer in Producer-Consumer

    A temporary data storage area used for communication between producer and consumer tasks.

    Signup and view all the flashcards

    PRODUCER task

    A task that generates data and places it into the buffer.

    Signup and view all the flashcards

    CONSUMER task

    A task that retrieves and processes data from the buffer.

    Signup and view all the flashcards

    BUFFER_SIZE

    The maximum number of items that the buffer can hold.

    Signup and view all the flashcards

    SELECT statement

    Allows choosing between multiple options based on conditions in concurrent programming.

    Signup and view all the flashcards

    BUFFER_EMPTY

    A boolean variable indicating if the buffer has no items.

    Signup and view all the flashcards

    PRODUCER_IS_DONE

    A boolean flag indicating if the producer has finished generating data.

    Signup and view all the flashcards

    Study Notes

    Programming Languages

    • PL/I: First attempt at a language suitable for many applications, developed by IBM in 1963. It incorporated the best aspects of Algol 60 (block structure and recursion), Fortran IV (separate compilation, global data communication), and COBOL (data structures, input/output, report generation). A large language with many features, including concurrent subprogram execution, exception handling (23 types), efficient linking for non-recursive subprograms, pointers, and array cross-sections.

    PL/I Example Program

    • Input: An integer (list length) followed by that many integers. The input list length must be less than 100.
    • Output: The count of input values greater than the average of all input values.
    • Program Structure: Features declarations of variables as fixed-point numbers, a section to read input data to the array, compute the sum, and then the average. It calculates the count of values greater than the average, and prints the final result.

    APL and SNOBOL

    • APL: Designed circa 1960 at IBM; published in 1962 in the book "A Programming Language". A language with many strong but potentially complex operators. Difficult to maintain.
    • SNOBOL: Developed in the early 1960s, intended for text processing. Features powerful operations that make pattern recognition in strings effective.

    SIMULA 67

    • Developed between 1962 and 1964. Originally designed for simulations, it evolved into a general-purpose language by 1967. Extensions of Algol 60. Introduced coroutines and the class construct.

    C

    • Developed at Bell Laboratories in 1972. Based on earlier languages including CPL, BCPL, B, and Algol 68. Designed to implement the UNIX operating system. First standardized as ANSI C in 1989 and updated in 1999 (C99). Lacks comprehensive type checking.

    C Example Program

    • Input: An integer (list length) followed by that many integers. The input list length must be less than 100.
    • Output: The count of input values greater than the average of all input values.
    • Program Structure: Contains input data to an array, computation of the sum and average, followed by counting values greater than average, and finally outputting the result.

    C++

    • An object-oriented extension of C, focused on the addition of classes and inheritance without a performance penalty. Features developed in stages (C with Classes in 1983, virtual methods in 1984, then multiple inheritance, abstract classes, templates, and exception handling in later releases.)

    C++ Features

    • Supports procedural and object-oriented programming.
    • Multiple inheritance.
    • Operator overloading.
    • Virtual methods.
    • Class/method templates.
    • Exception handling.
    • A popular and complex language, inheriting some of C's vulnerabilities.

    Prolog

    • A logic programming language that draws upon predicate calculus to define programs. Not procedure-oriented. Defines results rather than how to compute them. Uses facts and rules written as statements.
    • Uses resolution (prove method) for query evaluations.

    Ada

    • Developed in 1980 by the U.S. Department of Defense (DoD) amid the need for a more suitable language than the 450+ they were using. A language for embedded systems design. Initial specification release in 1975 in ACM publication. Standardized in 1983.
    • Major aspects: Any participant could contribute to improvements; the goal of the design process adhered to late 1970s software engineering concepts, and large-scale development. Early versions were highly complex, but Ada 95 and 2005 versions feature significant improvements, e.g., multiple inheritance, polymorphism, improved data sharing for concurrent processes, and reduced DoD reliance on Ada in its military software.

    Ada Example Program

    • Input: An integer (list length) followed by that many integers (less than 100).
    • Output: A count of input values greater than the average of all values.
    • Program Structure: Declares variables, takes in the input length, validates the length, reads in the data to an array, computes sum and averages. It calculates the count of values greater than the average, and prints the final result.

    Ada Tasks (Concurrency)

    • Ada supports concurrent operations with "tasks." The given example uses tasks for producer-consumer problems within a buffer. The program shows how tasks can be defined, initialized, and used to efficiently share resources. One task (sender) produces data, another (consumer) receives it, and a buffer manages transmission.

    Smalltalk

    • A pure object-oriented language. Smalltalk objects make up the totality of operations. Initial form, Smalltalk-72, made substantial use of Xerox Alto hardware. Smalltalk-80 improved the language design.
    • Features: Everything is an object; computing through messages to objects, a reply to the message also being an object, classes for object abstraction, and graphical user interfaces.

    Smalltalk Example Program

    • This program is creating the Polygon Class using the concept of inheritance from the Object class. Instance variables define characteristics. Methods to create instances and draw the polygons are specified.

    Java

    • Based on C++, but enhanced for additional power and flexibility, while being simpler and safer. Developed by Sun Microsystems in 1990 for embedded consumer applications. The primary goal was reliability.

    C#

    • Built on C++ and Java ideas, adding features such as enum types and operator overloading, reintroduced from previous languages that had been removed from Java. C# has a superior safety profile compared to C++.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    COSC 2P05 - Programming Languages (Week 2) PDF

    Description

    Explore the fundamentals of PL/I, a language developed by IBM in 1963, designed for various applications. This quiz assesses your understanding of PL/I's unique features such as exception handling, concurrent subprogram execution, and its ability to manage data structures effectively.

    More Like This

    Exception Handling in Programming Quiz
    47 questions

    Exception Handling in Programming Quiz

    GratifiedPearl avatar
    GratifiedPearl
    Programming Loops Quiz
    40 questions

    For Loops Quiz: Test Your Programming Skills

    GratifiedPearl avatar
    GratifiedPearl
    PL/I Programming Language Quiz
    10 questions

    PL/I Programming Language Quiz

    SpeedyBliss avatar
    SpeedyBliss
    PL/SQL Concepts and Programming Quiz
    16 questions

    PL/SQL Concepts and Programming Quiz

    DazzlingKremlin2019 avatar
    DazzlingKremlin2019
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser