Difference between revisions of "BNF - Syntax Diagrams"

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

Revision as of 10:11, 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.