Difference between revisions of "BNF - Syntax Diagrams"

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Backus Naur Form is a way of describing the syntax of a value to form a new value. <br />
 
Backus Naur Form is a way of describing the syntax of a value to form a new value. <br />
For example:
+
For example: <br />
<digit> ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
+
<digit> ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 <br />
 
This declares that <digit> can only be the numbers 0-9, specifically 0 OR 1 OR 2 OR 3 etc.
 
This declares that <digit> can only be the numbers 0-9, specifically 0 OR 1 OR 2 OR 3 etc.
  

Revision as of 09:11, 16 May 2017

Backus Naur Form is a way of describing the syntax of a value to form a new value.
For example:
<digit> ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
This declares that <digit> can only be the numbers 0-9, specifically 0 OR 1 OR 2 OR 3 etc.

This notation can also be recursive: <integer> ::= <digit> | <digit><integer> This states that an integer can be a digit or a digit followed by another integer.