Computer Languages



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Script Languages

  1. AWK


Aho Weinberger Kernighan) A UNIX programming utility developed in 1977 by Alfred Aho, Peter Weinberger and Brian Kernighan. Due to its unique pattern-matching syntax, awk is often used in data retrieval and data transformation. Awk is widely used to search for a particular occurrence of text and perform some operation on it. Awk is an interpreted language, which has been ported to other computing environments, including DOS. See Gawk.

      1. CGI


(Common Gateway Interface script) A small program written in a language such as Perl, Tcl, C or C++ that functions as the glue between HTML pages and other programs on the Web server. For example, a CGI script would allow search data entered on a Web page to be sent to the DBMS (database management system) for lookup. It would also format the results of that search as an HTML page and send it back to the user. The CGI script resides in the server and obtains the data from the user via environment variables that the Web server makes available to it.

CGI scripts have been the initial mechanism used to make Web sites interact with databases and other applications. However, as the Web evolved, server-side processing methods have been developed that are more efficient and easier to program. For example, Microsoft promotes its Active Server Pages (ASPs) for its Windows Web servers, and Sun/Netscape nurtures its Java roots with JavaServer Pages (JSPs) and servlets. See ASP, JSP, servlet and FastCGI.





Web Server Evolution
Starting at the top and moving down, this illustration shows Web and application server processing as it evolved initially using only CGI scripts and later using Java components. The separation of logic is portrayed here, and the Web server (HTTP server) and application server may reside in the same or different computers.

      1. JAVAScript


A popular scripting language that is widely supported in Web browsers and other Web tools. It adds interactive functions to HTML pages, which are otherwise static, since HTML is a display language, not a programming language. JavaScript is easier to use than Java, but not as powerful and deals mainly with the elements on the Web page. On the client, JavaScript is maintained as source code embedded into an HTML page. On the server, it is compiled into bytecode (intermediate language), similar to Java programs.

JavaScript evolved from Netscape's LiveScript language. First released with Navigator 2.0, it was made more compatible with Java. JavaScript does not have the programming overhead of Java, but can be used in conjunction with it. For example, a JavaScript script could be used to display a data entry form and validate the input, while a Java applet or Java servlet more thoroughly processes the information. JavaScript is also used to tie Java applets together. See JScript, Java, Java applet, servlet and VBScript.


      1. Perl


(Practical Extraction Report Language) A programming language written by Larry Wall that combines syntax from several UNIX utilities and languages. Introduced in 1987, Perl is designed to handle a variety of system administrator functions and provides comprehensive string handling functions. It is widely used to write Web server programs for such tasks as automatically updating user accounts and newsgroup postings, processing removal requests, synchronizing databases and generating reports. Perl has also been adapted to non-UNIX platforms. See also PURL.

      1. PHP


(PHP Hypertext Preprocessor) A scripting language used to create dynamic Web pages. With syntax from C, Java and Perl, PHP code is embedded within HTML pages for server side execution. It is commonly used to extract data out of a database and present it on the Web page. The major NT and UNIX Web servers support the language, and it is widely used with the mSQL database. PHP was originally known as "Personal Home Page." See mSQL

      1. Python


http://www.python.org

      1. Shells


Unix/Linux shells:

Bourne shell.

Bourne Again SHell.

C shell.


Korn shell.

DOS shell

4DOS, 4OS2.

      1. VBScript


(Visual Basic SCRIPT) A scripting language from Microsoft. A subset of Visual Basic, VBScript is widely used on the Web for both client processing within a Web page and server-side processing in Active Server Pages (ASPs). As an ActiveX scripting language, VBScript is also used with the Windows Script Host (WSH) to perform functions locally on a Windows machine. See JScript and ASP.

  1. Structures


Program: Main, Subprogram.

Order: Preprocessor, Declaration, Statements.

2. Syntax: Continuation, Case, Comments.

File: external.

Source Files-> Object Files

a. Executables

b. Libraries ( Static / Dynamic )

  1. Variables

    1. Types


Integers.

Floating Points.

Characters.

Bits.


Pointers.

    1. Modifiers


Long, short, double, …

    1. Scopes


Local

global

    1. Duration


Permanent.

Transient.


    1. Declaration & Allocation

    2. Organized


Arrays / Strings.

Structures.

Classes

  1. Operators

    1. Arithmic


+, -, *, /, % …

    1. Relational


>, <, = =, …

    1. Logic


&&, ||, !

    1. Bitwise


&, |, ^, <<, >>, ~

    1. Miscellaneous


+ +, - -, ? :, …

    1. Precedence

  1. Flow Control

    1. Decision


IF … THEN … ELSE.

SWITCH … CASE.

GOTO.

    1. Loop


FOR.

DO … END DO

DO … WHILE

BREAK, CONTINUE.


  1. Functions


Returned value.

Arguments: Call by value, Call by reference.

Variables: local, global, external.

static, transient.

Entry point, Return point.

Recursive, Variable argument list.

System Calls

  1. Preprocessors


#define

#include

  1. I/O


Files.

Devices.


Format.

Buffer.


Pipes & Filters

  1. OOP


http://vtopus.cs.vt.edu/~kafura/cs2704/Notes.html
Classes & Objects:

Data Encapsulation.

Privacy & Friends.

Operator Overload.

Derivation and Inheritance.

  1. Functional Programming


http://www.cs.nott.ac.uk/~gmh//faq.html#functional-languages

A. Cumming: A Gentle Introduction to ML

André van Meulebrouck’s Lambda Calculus Tutorial

  1. Reflection


http://tunes.org/Review/Reflection.html

  1. GUI

    1. Visual Basic


A version of the BASIC programming language from Microsoft specialized for developing Windows applications. When first released in 1991, Visual Basic was similar to Microsoft's QuickBASIC. By the mid 1990s, it became extremely popular. User interfaces are developed by dragging objects from the Visual Basic Toolbox onto the application form.

Visual Basic (VB) is widely used to write client front ends for client/server applications. As of Version 5.0, it is also used to create ActiveX controls for the Web (both EXE's and DLL's). Visual Basic for Applications (VBA) is a subset that provides a common macro language included with many Microsoft applications.



Up until VB 5, the Visual Basic compiler only converted the source code written by the programmer into an intermediate language called "bytecode." Starting with VB 5, native executable programs can be generated. No matter what the version, in order to run a VB program, the VB runtime module, must reside in the target computer. This .DLL file, named VBRUNxxx (up to VB 4) or MSVBVMxx (VB 5 and after), where x is the version number, contains necessary runtime libraries and also converts programs compiled to bytecode into the machine language of the computer. The runtime DLLs are widely available and typically accompany a Visual Basic application. See compiler and VBScript.



Visual Basic Is Interpreted
Visual Basic is similar to Java. It is compiled into an intermediate language called "bytecode." The bytecode is translated into x86 machine language by the Visual Basic runtime module. Starting with VB 5, native executable (.EXE files) can also be generated, but the runtime module, which provides necessary runtime functions, must still reside in the target computer.
Tutorials: http://www.vbweb.co.uk/vb/

    1. Visual C++


A C and C++ development system for DOS and Windows applications from Microsoft. It includes Visual Workbench, an integrated Windows-based development environment and Version 2.0 of the Microsoft Foundation Class Library (MFC), which provide a basic framework of object-oriented code to build an application upon.

Introduced in 1993, the Standard Edition of Visual C++ replaces QuickC for Windows and the Professional Edition includes the Windows SDK and replaces Microsoft C/C++ 7.0.


    1. VisualAge


A family of object-oriented application development software from IBM that includes VisualAge for Basic, VisualAge for C++, VisualAge for COBOL, VisualAge for Java, VisualAge for PacBase and VisualAge for Smalltalk. For example, VisualAge for C++ is a multiplatform environment for writing C++ applications for OS/2, Windows, AS/400, MVS/ESA, AIX and Solaris. It is widely used to write an application on one platform that will be used on another.

Today, the skills of a VisualAge programmer are not implicit, as the term refers to several languages. In the past it implied one or two. The VisualAge name was first used in the late 1980s for Smalltalk, then in 1994 for C++ and later for all the others. Nevertheless, all the VisualAge languages are themselves written in IBM's Smalltalk. See Smalltalk.


    1. TCL/TK


(Tool Command Language/ToolKit) Pronounced "tickle" or "ticklet," it is an interpreted script language that is used to develop a variety of applications, including GUIs, prototypes and CGI scripts. Created for the UNIX platform by John Ousterhout along with students at the University of California at Berkeley, it was later ported to PCs and Macs. Safe-Tcl is an enhanced Tcl interpreter that provides a secure, virus free environment.

Tcl also provides an interface into compiled applications (C, C++, etc.). The application is compiled with Tcl functions, which provide a bi-directional path between Tcl scripts and the executable programs. Tcl provides a way to "glue" program modules together. The Tk part of Tcl/Tk is the GUI toolkit, which is used to create graphical user interfaces. Other languages, including Perl, Python and Scheme, have incorporated Tk as well.


Starting Point:

http://www.geocities.com/lvirden/tcl-faq/

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