ТОП 10:

S. B: Most high-level languages are machine oriented. – S. B: No, this is false. Most high-level languages are machine independent. Assembler is machine oriented.



 

1. Programming in machine language involves the difficult task of writing instructions in the form of strings of binary digits.

2. An assembler language uses symbols.

3. High-level language programs are usually more efficient that assembler language programs.

4. Machine languages are the most basic level of programming languages.

5. In high-level languages the potential for error is reduced.

 

III. Complete the following sentences using words and expressions given below.

1. Each programming language has its own unique … … and … .

2. Necessity to write long series of instructions in the form of binary digits makes machine language programming an … … .

3. Assembler languageswere developed to … the difficulties in writing machine language programs.

4. Assembler allows the computer to … instructions into machine instructions.

5. Assembler language is machine … .

6. High-level language programs require a … amount of computer time for translation into machine instructions.

 

language rules syntax oriented greater reduce error-prone task convert

 

IV. Fill in the prepositions if necessary.

Java is a programming language originally developed … Sun Microsystems and released … 1995 as a core component of Sun's Java platform. The language derives much of its syntax … C and C++ but has a simpler object model and fewer low-level facilities. Java applications are typically compiled to bytecode which can run … any Java virtual machine (JVM) regardless … computer architecture.

The original and reference implementation of Java compilers, virtual machines, and class libraries were developed … Sun from 1995. … May 2007, in compliance … the specifications of the Java Community Process, Sun made available most of their Java technologies as free software … the GNU General Public License. Others have also developed … alternative implementations of these Sun technologies, such as the GNU Compiler for Java and GNU Classpath.

 

 

V. Answer the questions.

1. What is a machine code?

2. What can cause many errors?

3. What languages are called the first-generation languages?

4. Why are machine languages very tedious and exacting?

5. What does programming in machine languages require?

6. What makes machine language programming a difficult and error-prone task?

7. Why were assembler languages developed?

8. Why are they called symbolic languages?

9. What are advantages of assembler language?

10. What are disadvantages of assembler language?

11. What instructions do high-level languages use?

12. What are advantages and disadvantages of high-level languages?

 

Read the text.

 

Icon is a high-level programming language with extensive facilities for processing strings and structures. Icon has several novel features, including expressions that may produce sequences of results, goal-directed evaluation that automatically searches for a successful result, and string scanning that allows operations on strings to be formulated at a high conceptual level. Icon also provides high-level graphics facilities.
Icon emphasizes high-level string processing and a design philosophy that allows ease of programming and short, concise programs. Storage allocation and garbage collection are automatic in Icon, and there are few restrictions on the sizes of objects. Strings, lists, and other structures are created during program execution and their size does not need to be known when a program is written. Values are converted to expected types automatically; for example, numeral strings read in as input can be used in numerical computations without explicit conversion. Icon has an expression-based syntax with reserved words; in appearance, Icon programs resemble those of Pascal and C.
Although Icon has extensive facilities for processing strings and structures, it also has a full repertoire of computational facilities. It is suitable for a wide variety of applications. Some examples are:

text analysis

text editing

document formatting

artificial intelligence

expert systems

rapid prototyping

symbolic mathematics

text generation

data laundry.

 

 

Fourth-Generation Languages

 

The term fourth-generation language describes a variety of programming languages that are more nonprocedural and conversational that prior language. These languages are called fourth-generation languages (4GLs) to differentiate them from machine languages (first generation), assembler languages (second generation), and high-level languages (third generation).

Most fourth-generation languages are nonprocedural languages that encourage users and programmers to specify the result they want, while the computer determines the sequence of instructions that will accomplish those results. Users and programmers no longer have to spend a lot of time developing the sequence of instructions the computer must follow to achieve a result. Thus, fourth-generation languages have helped simplify the programming process. Whereas a fourth-generation language program must follow a specific set of rules and syntax, a natural program does not. A natural language, sometimes called a fifth-generation language, is a type of query language that allows the user to enter requests that resemble human speech. Research and development activity in artificial intelligence is developing programming languages that are as easy to use as ordinary conversation in one’s native tongue.

Advantages and Disadvantages. There are major differences in the ease of use and technical sophistication of 4GL products. For instance, INTELLECTand English Wizard are examples of natural query languages that impose no rigid grammatical rule, while languages like SQL requires concise structured statements. However, the ease of use of 4GLs is gained at the expense of some loss in flexibility. It is frequently difficult for an end user to override some of the prespecified formats or procedures of 4GLs. In addition, the machine languages code generated by a program developed by a 4GL is frequently much less efficient (in terms of processing speed and amount of storage capacity needed) that a program written in a languages like COBOL. Major failures have occurred in some large transaction processing applications programmed in a 4GL. These applications were unable to provide reasonable response times when faced with a large amount of real-time transaction processing and end user inquiries. However, 4GLs have shown great success in business applications that do not have a high volume of transaction processing.

 

Comments:

nonprocedural language не процедурна мова//мови програмування, які

ґрунтуються не на послідовно виконуваних

операторах, а на описі набору (бази) фактів і

відношень (правил), за якими виводиться відповідь

на поставлене запитання

concise короткий, стислий; чіткий, виразний

to override скасовувати; відхиляти

SQL Structured мова структурованих запитів, мова SQL

Query Language мова запитів

I.Match the words in the text with their definitions:

1.To differentiate A. The amount that something can hold or

contain.

2.To gain B. To obtain (something useful, wanted,

profitable, etc.).

3. To specify C. Not too much too many or too great.

4. Reasonable D. To see or to express a difference

(between).

5. Capacity E. To state exactly.

 

II. Identify whether the following sentences are true or false. Use the model:

Student A: A natural language is a type of query language that allows the user to enter requests that resemble human speech. – Student B: Yes, this is really so.

S. A: INTELLECT and English Wizard are examples of natural query languages that require rigid grammatical rules. – S. B: I think you are wrong. I fact, these languages impose no rigid grammatical rules.

 

1. Most fourth-generation languages are procedural languages.

2. Fourth-generation languages have helped simplify the programming process.

3. 4GLs are very different from English or other human languages.

4. There are no differences in the ease of use and technical sophistication of 4GL products.

5. The machine languages code generated by a program developed by a 4GL is frequently much less efficient that a program written in a languages like COBOL.

 







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