Difference between revisions of "BNF - Syntax Diagrams"

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==BNF==
 
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: <br />
 
For example: <br />
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<integer> ::= <digit> | <digit><integer> <br>
 
<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.
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==Syntax Diagrams==
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These are a diagram approach similar to BNF, they also describe the syntax allowed.
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[[File:syntaxdiagram.gif]]

Revision as of 20:05, 21 May 2017

BNF

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.

Syntax Diagrams

These are a diagram approach similar to BNF, they also describe the syntax allowed.

Syntaxdiagram.gif