Found 146 Articles for Compiler Design

The major operations on sequential files are as follows −Creating a file − The primary creation of a file is also defined as the loading of the file. In some implementations, space is first designated to the file, thus the data are loaded into that Skelton.Opening a file − Before a program can access a file for input or output, that file must be opened. The open operation is given the name of a file and the access mode (read or write). In Pascal, the procedure reset opens a file in read mode and the procedure rewrite opens a file ... Read More

The major attributes for specifying data structures include the following −Number of components − A data structure can be of fixed size if the number of components is even during its lifetime or of the variable size if the number of components transforms dynamically. Variable size data structure types generally define operations that insert and delete elements from structures.Arrays and records are examples of fixed-size data structure types. Stacks, lists, sets, tables, and files are an example of variable size data types. Variable size data objects use a pointer data type that enables fixed-size data objects to be connected explicitly ... Read More

The set of operations defined for a data type decided how data objects of that type can be manipulated. The operations can be primitive operations, which defines they are stated as an element of the language definition or they can be programmer-defined operations, as an element of class definitions.An operation is a mathematical function, for a given input argument and it has a clear and simply persistent result. Each operation has a domain (the set of possible results that it can create). The action of the operation represents the results created for any given set of arguments.The elements that combine ... Read More

Type checking is the activity of providing that the operands of an operator are of compatible types. A compatible type is one that is legal for the operator or is enabled under language rules to be implicitly modified by compiler-generated code to a legal type. This automatic conversion is known as coercion. If all binding of variables to type is dynamic in a language, thus type checking can virtually continually be completed dynamically. The dynamic type checking is done during program execution.The dynamic type checking is generally executed by saving a type tag in each data object that expresses the ... Read More

A programming language is an artificial language that can control the behaviour of a machine, specifically in computers. Programming language like natural languages is defined by syntactic and semantic rules which define their structure and meaning respectively. The hierarchical structure of programming languages is as follows −Programs − Computer programs are instructions for a computer. A computer needed programs to function, generally executing the program’s instructions in the main processor. The program has an executable form that the computer can use directly to execute the instructions. The equivalent program in its human-readable source program form, from which executable programs are ... Read More

One-Pass CompilerOne pass compiler reads the code only once and then translates it. The one-pass compiler passes only once through the parts of each compilation unit. It can translate each part into its final machine program. In the one-pass compiler, when the line source is processed, it is scanned and the token is extracted. This is in contrast to a multi-pass compiler which modifies the program into one or more intermediate representations in steps between source program and machine program, and which convert the whole compilation unit in each sequential pass.A one-pass compiler is fast since all the compiler code ... Read More

The Chomsky hierarchy is a collection of various formal grammars. With the use of this formal grammar, it can generate some formal languages. They can be defined by multiple types of devices that can identify these languages such as finite state automata, pushdown automata, linear bounded automata, and Turing machines, respectively.Chomsky has suggested four different classes of phrase structure grammar as follows −Type-0 Grammar (Unrestricted Grammar) − Type-0 grammar is constructed with no restrictions on the replacement rule. A non-terminal must appear in the string on the left side. The language generated is called recursively enumerable language.Thus, type-0 grammar isAn ... Read More

The binding of a program element to a specific characteristic or property is the choice of the property from a set of possible properties. The time during program organization or processing when this choice is made is defined as the binding time of that property for that element. There are multiple varieties of bindings in programming languages, and a variety of binding times. It can also involve within the terms of binding and binding time the properties of program elements that are constant either by the definition of the language or its execution.Types of Binding TimesThere are two types of ... Read More

Programming environments have affected language design generally in two major areas such as features promoting separate compilation and assembly of a program from components, and features aiding program testing and debugging.Separate compilation − In the structure of any huge program it is regularly desirable to have multiple programmers or programming group design, code, and test elements of the program before the last assembly of all the elements into a complete program. This needed the language to be structured so that single subprograms or other elements can be separately compiled and implemented, without the other element, and thus later combined without ... Read More

The type conversion is an operation that takes a data object of one type and creates the equivalent data objects of multiple types. The signature of a type conversion operation is given as                   conversion_op :type1→type2There are two types of type conversions which are as follows −Implicit type conversion (Coercions) − The programming languages that enable mixed-mode expressions should describe conventions for implicit operand type conversions.Coercion is defined as an automatic conversion between types. For example in Pascal, if the operands for the addition operation are of integer type and other real types, ... Read More