Pascal programming language

Pascal is an imperative programming computer programming programming language, developed in 1970 by Niklaus Wirth as a language particularly suitable for structured programming.

Pascal is based on the ALGOL programming language and named in honor of mathematician and philosopher Blaise Pascal. Wirth also developed Modula-2 and Oberon programming language, languages similar to Pascal. Oberon also supports object-oriented programming.

Initially, Pascal was a language intended to teach students structured programming, and generations of students have cut their teeth on Pascal as an introductory language in undergraduate courses. Variants of Pascal are still widely used today, both in education and software development.

Much of the original Apple Macintosh operating system was written in Pascal. The popular typesetting system TeX is written in a language named WEB for which Donald Knuth borrowed heavily from Pascal.

= Language =

All Pascal programs start with the Program keyword, an optional list of external file descriptors and then a block of code is indicated with the Begin and End keywords. Semicolons separate statements, and the full stop ends the program (or unit). Letter case is ignored in Pascal source.

program HelloWorld(output); begin writeln( Hello, World! ) end.

Pascal, in its original form, is a purely procedural language with the standard array of if, while, for, and related constructs.

Pascal is a structured programming language, meaning that the flow of control is structured into standard statements, ideally without goto (command) commands.

while a b do WriteLn( Waiting ); if a > b then writeln( Condition met ) else writeln( Condition false ); for i := 1 to 10 do writeln( Iteration: , i:1); repeat a := a + 1 until a = 10;

Pascal structures programs into procedures and functions.

program mine(output); procedure print(var i: integer); function next(i: integer): integer; begin next := i + 1 end; begin writeln( The total is: , i); i := next(i) end; begin i := 1; while i