1. What are the different Language Evaluation Criteria?
A language evaluation criterion is broadly used to measure how usable a programming language is. This includes four main criteria and many characteristics alongside. Readability: defines the ease of understandability of a programming language. Include many factors such as below. * Simplicity – strongly affects readability. A language with few basic constructs is much easier to learn. Feature multiplicity and operator overloading are potential problems of simplicity. * Orthogonality – a language with few primitive constructs can only be combined in small number of ways to create the control and data structures. Relatively close to simplicity, the more orthogonal a language is, the fewer exceptions required. This means better readability and easier understandability. * Data types – ability to define adequate types of data structures is important. If there was no Boolean type data structure, we might have to use 1, 0 as true or false but this affects readability. * Syntax design – how the syntax is designed is important for readability in ways such as defining identifier forms. If identifiers can define into descriptive names, it facilitates readability. Another factor is the language’s special words. Words reserved for specials purposes quickly indicates reader to what is beginning or end and control. Writability: measures how easy to program software using the certain language. Following characteristics influences writability. * Simplicity and orthogonality – combing fewer primitive constructors into different ways simplifies writability. But too many orthoganility may cause to errors go undetected. * Support for Abstraction – using abstraction, language has the ability to hide complex operation structures details. You may abstract an operation into a method that get to used several times in a program and only use the method calling in those places. Abstraction can be in two different categories as process and data. * Expressivity – ability of having many ways of specifying a computation such as ‘i++’ rather than ‘i=i+1’. Facility to express certain code in different convenient ways can be called expressivity.
Reliability: if a program performs to tis specifications under all conditions, it called reliable. Here follows some effective characteristics affects to reliability. * Type checking – testing for type errors while compiling or during execution. Very important factor of reliability. * Exception handling – the ability of countermeasure runtime errors and continue the program is very important to reliability. * Aliasing – ability to address same memory location using many distinct names is aliasing. In some languages, aliasing used to overcome data structure deficiencies. * Readability and Writability – both of these also influence the reliability. Cost: the cost of a program language may seem blurry but it does measure. Some characteristics are mentioned below. * Cost of training programmers to use the language. More orthogonal the language, less cost this may have. * Writing programs in the language
* Compiling programs in language
* Cost of execution programs written in a language
* Cost of implementation system
* Cost of maintain system
2. What are the different Language categories?
Imperative Languages: usually procedure-oriented paradigm is used with imperative languages. Features include variables, assign statements and control statements. Examples for pure imperative languages are C, Perl, and Ruby. All the object-oriented paradigm based languages are evolved from imperative languages such as Java. There is subcategory as visual languages on the imperative languages. These visual languages gives ability of generate GUIs easily by drag and drop. All .NET languages such as VB.NET and C++, C# categorized into here. Scripting languages...