Obyx

The Comparison Function

Comparison is a flow control function which allows a comparison to occur between one or more comparate values, and processes a defined true or [false] value.

Where should it be used?

Comparison is commonly used for processing and validation of input data, or anywhere a decision must be made as to what the next action of the application should be.

Comparison attributes

• operation: Operation indicates the type of comparison which should be applied against the comparate values
• invert (false*/true): Invert gives the opposite result returned from the comparison
• logic (all*/any): logic (any) returns true if any comparate meets the criteria. The default (all) requires all comparates to meet the criteria.

break (true*/false): break (true) stops evaluating comparates as soon as the result is available. For instance, with an equal test over twenty comparates, as soon as there are two comparates that are not equal, the comparison operation no longer needs to continue to evaluate comparates in order to complete.)

Operation types

• equal *: Returns true if thecomparate values are the same as one another
• existent: Returns true if the comparate values exist (useful for testing [sysparm]s for existance)
• empty: Returns true if the comparates are empty
• found: Returns true if the comparate values are found using the space and the regex value.
• significant: Returns true if the comparate values exist and are not empty.
• true: Returns true if the comparates return ('true')
• lesser: Returns true if the first comparate is greater than all subsequent comparates
• greater: Returns true if the first comparate is less than all subsequent comparates

Visual Guide to the Comparison function

See also:

• flow-function
• output
• control
• body

Examples of equal

<comparison>
	<comparate>green<@L(!docComparate)>
	<comparate>green<@L(!docComparate)>
	<ontrue>They're the same!</ontrue>
	<onfalse>They're different!</onfalse>
</comparison>

They're the same!

<comparison>
	<comparate>green<@L(!docComparate)>
	<comparate>blue<@L(!docComparate)>
	<comparate>green<@L(!docComparate)>
	<ontrue>They're the same!</ontrue>
	<onfalse>They're different!</onfalse>
</comparison>

They're different!

Example of existent

<instruction>
	<output type="store" value="myStore" />
	<input>Contents!</input>
</instruction>
<comparison operation="existent">
	<comparate type="store" value="myStore" />
	<ontrue>myStore Exists!</ontrue>
	<onfalse>myStore is only a figment of my imagination...</onfalse>
</comparison>

myStore Exists!

Example of empty

<instruction>
	<output type="store" value="myStore" />
	<input>Test test test</input>
</instruction>
<comparison operation="empty">
	<comparate type="store" value="myStore" />
	<ontrue>I'm empty</ontrue>
	<onfalse>I'm full!</onfalse>
</comparison>

I'm full!

Example of significant

<c:comparison operation="significant">
	<c:comparate value="cat" />
	<c:ontrue>Yes I am</c:ontrue>
	<c:onfalse>No I'm not</c:onfalse>
</c:comparison>

Yes I am

Examples of found

<c:comparison operation="found" note="assume that there IS a file called book.xml">
	<c:comparate space="file" value=".ook\.xml" />
	<c:ontrue value="true" />
	<c:onfalse value="false" />
</c:comparison>

true

Example of lesser

<c:comparison operation="lesser">
	<c:comparate value="7" />
	<c:comparate value="3" />
	<c:comparate value="7" />
	<c:ontrue value="seventh heaven" />
	<c:onfalse value="seven sins" />
</c:comparison>

seven sins

Example of greater

<c:comparison operation="greater">
	<c:comparate value="9" />
	<c:comparate value="6" />
	<c:ontrue value="Why yes, that is greater..." />
	<c:onfalse value="Just plain appaling" />
</c:comparison>

Why yes, that is greater...

<comparison>
	<comparate>100</comparate>
	<ontrue>My o's are rounder than your 0's</ontrue>
	<onfalse>I'm afraid not</onfalse>
</comparison>

My o's are rounder than your 0's