Editing Extended Backus–Naur form (section)

===Pascal===
A [[Pascal (programming language)|Pascal]]-like programming language that allows only assignments can be defined in EBNF as follows:

<syntaxhighlight lang="ebnf">
 (* a simple program syntax in EBNF - Wikipedia *)
 program = 'PROGRAM', white space, identifier, white space, 
            'BEGIN', white space, 
            { assignment, ";", white space },
            'END.' ;
 identifier = alphabetic character, { alphabetic character | digit } ;
 number = [ "-" ], digit, { digit } ;
 string = '"' , { all characters - '"' }, '"' ;
 assignment = identifier , ":=" , ( number | identifier | string ) ;
 alphabetic character = "A" | "B" | "C" | "D" | "E" | "F" | "G"
                      | "H" | "I" | "J" | "K" | "L" | "M" | "N"
                      | "O" | "P" | "Q" | "R" | "S" | "T" | "U"
                      | "V" | "W" | "X" | "Y" | "Z" ;
 digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ;
 white space = ? white space characters ? ;
 all characters = ? all visible characters ? ;
</syntaxhighlight>

For example, a syntactically correct program then could be:
<syntaxhighlight lang="pascal">
 PROGRAM DEMO1
 BEGIN
   A:=3;
   B:=45;
   H:=-100023;
   C:=A;
   D123:=B34A;
   BABOON:=GIRAFFE;
   TEXT:="Hello world!";
 END.
</syntaxhighlight>

The language can easily be extended with [[control flow]]s, arithmetical expressions, and Input/Output instructions. Then a small, usable programming language would be developed.