learnxinyminutes-docs/pascal.html.markdown

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---
language: Pascal
filename: learnpascal.pas
contributors:
- ["Ganesha Danu", "http://github.com/blinfoldking"]
---
>Pascal is an imperative and procedural programming language, which Niklaus Wirth designed in 196869 and published in 1970, as a small, efficient language intended to encourage good programming practices using structured programming and data structuring. It is named in honor of the French mathematician, philosopher and physicist Blaise Pascal.
source : [wikipedia](https://en.wikipedia.org/wiki/Pascal_(programming_language))
to compile and run a pascal program you could use a free pascal compiler. [Download Here](https://www.freepascal.org/)
```pascal
//Anathomy of a Pascal Program
//this is a comment
{
this is a
multiline comment
}
//name of the program
program learn_pascal; //<-- dont forget a semicolon
type
{
this is where you should delcare a custom
data-types
}
var
{
this is where you should declare a variable
}
//main program area
begin
{
area to declare your instruction
}
end. // End of a main program area should required a "." symbol
```
```pascal
//declaring variable
//you can do this
var a:integer;
var b:integer;
//or this
var
a : integer;
b : integer;
//or this
var a,b : integer;
```
```pascal
program Learn_More;
//Lets learn about data types and their operations
//Declaring variables
var
int : integer; // a variable that contains an integer number data types
ch : char; // a variable that contains a character data types
str : string; // a variable that contains a string data types
r : real; // a variable that contains a real number data types
bool : boolean; //a variables that contains a Boolean(True/False) value data types
Begin
int := 1;// how to assign a value to a variable
r := 3.14;
ch := 'a';
str := 'apple';
bool := true;
//pascal is not a case-sensitive language
//arithmethic operation
int := 1 + 1; // int = 2 overwriting the previous assignment
int := int + 1; // int = 2 + 1 = 3;
int := 4 div 2; //int = 2 a division operation which the result will be floored
int := 3 div 2; //int = 1
int := 1 div 2; //int = 0
bool := true or false; // bool = true
bool := false and true; // bool = false
bool := true xor true; // bool = false
r := 3 / 2; // a division operator for real
r := int; // you can assign an integer to a real variable but not the otherwise
c := str[1]; // assign the first letter of str to c
str := 'hello' + 'world'; //combining strings
End.
```
```pascal
```