Difference between revisions of "Validate Script"

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The pre-requisite test can be anything you want, provided only the object and the container are considered by the test. The requirement is always either satisfied or not satisfied. This is determined by the "valid" special symbol. The symbol starts out as zero, indicating that the requirement is not satisfied. At any point during the script, you can set the symbol to non-zero, thereby indicating that the requirement '''is''' satisfied. The only value that matters is the final value when the script ends, where a non-zero value indicates the pre-requisite is satisfied.
 
The pre-requisite test can be anything you want, provided only the object and the container are considered by the test. The requirement is always either satisfied or not satisfied. This is determined by the "valid" special symbol. The symbol starts out as zero, indicating that the requirement is not satisfied. At any point during the script, you can set the symbol to non-zero, thereby indicating that the requirement '''is''' satisfied. The only value that matters is the final value when the script ends, where a non-zero value indicates the pre-requisite is satisfied.
  
Since an EvalRule script is equivalent to an Eval script, it '''is''' possible to apply changes throughout the structural hierarchy via the script. However, it is generally a bad idea to do that, since the purpose of an EvalRule script is to validate a rule - not effect change. We therefore recommend that you avoid applying changes within EvalRule scripts.
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Each pre-requisite is associated with a particular thing. If a pre-requisite is defined for a component, then it is inherited by the things which derive from that component. The pre-requisites are checked for every thing when it is presented as an option for the user to add via a table or chooser. If one or more pre-requisites are not satisfied, the thing is designated as invalid and the failed requirements are shown in the description information for the thing. If the thing is added by the user in spite of the failed pre-requisites, then all the pre-requisites are applied to the pick at the end of every evaluation cycle.
  
Since the message and summary are typically static requirements (e.g. an attribute must be a value of X or more), you will rarely need to modify them. However, there will be cases where you want to tailor the message and/or summary to provide more detailed information based on dynamic information. When this situations arise, simply set the "message" and/or "summary" special values to the desired contents and they will be used.
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When invoked, a Validate script starts with the container as its initial context. If the object is a pick, the container is the one the pick resides within. If the object is a thing, the container is the prospective container to which the thing will potentially be added. The reason for the container as the initial context is that the pre-requisite test is defined on the thing. Consequently, the thing will know about itself and will typically be looking to verify that the prospective container satisfies the needs of the thing.
  
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For those situations where you also need to access characteristics of the pick or thing, the Validate script provides an alternate context. This context will always be the pick or thing, as appropriate. You can use the "ispick" special symbol to determine whether the pre-requisite is being applied to a pick or a thing.
  
Like an Eval script, every EvalRule script is associated with a particular thing. If an EvalRule script is defined for component, then it is inherited by the things which derive from that component. When a thing is added to a container, it becomes a pick, and new instances of every EvalRule script for that thing are created and managed by HL. You associate all of the validation rules with each pick via the EvalRule scripts defined for the underlying thing.
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{{note}}The use of pre-requisites with a Validate script is generally only needed in more complex situations. The "pickreq" and "exprreq" mechanisms are much simpler to use and maintain, and they should cover 90% of the situations where you need to establish a pre-requisite.
 
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When invoked, an Eval script starts with its associated pick as its initial context. You are free to navigate through the hierarchy and test the state of anything that impacts the rule. However, a given EvalRule script should will typically either pertain to the associated pick or pertain to the actor as a whole.
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==Example==
 
==Example==
  
An EvalRule script can be used to test virtually anything. Within the Sample data files, a rule is used to ensure that pieces of gear are not both equipped and held within a container (e.g. a sword being equipped and stored in a backpack). The rule below will verify this condition.
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A simple pre-requisite might establish a dependency on an attribute value being at least equal to some number. The example below shows a Validate script that tests whether the container has a child pick (strength) that has a final value of at least 13.
  
 
<pre>
 
<pre>
~if not both equipped and held within a container, we're valid
+
if (child[attrStr].field[trtFinal].value >= 13) then
if (field[grIsEquip].value + isgearheld < 2) then
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   @valid = 1
 
   @valid = 1
  done
 
 
   endif
 
   endif
 
~mark the tab as invalid
 
linkvalid = 0
 
 
</pre>
 
</pre>

Revision as of 03:06, 14 December 2008

Context: HL KitKit Reference … Script Types 

Technical Details

Initial Context: Container
Alternate Context: Pick or Thing
Fields Finalized? Yes

The Validate script utilizes the following special symbols:

valid Entry: Assumes the pre-requisite is not satisfied with a value of zero.

Exit: Indicates whether the pre-requisite is satisfied (non-zero) or not satisfied (zero).

message Entry: Contains the default message text if the pre-requisite is not satisfied.

Exit: Contains the final message text to display if the pre-requisite is not satisfied.

ispick Entry: Indicates whether the pre-requisite is being applied to a pick (non-zero) or thing (zero).

Exit: Ignored.

Description

The Validate script is exclusively used within pre-requisite tests. The script verifies that a specific pick or thing satisfies a particular pre-requisite relative to its container. If the requirement is not satisfied, then the object is designated as invalid. If the object is a pick that has already been added to the portfolio, the specified message is displayed within the validation report for the actor.

The pre-requisite test can be anything you want, provided only the object and the container are considered by the test. The requirement is always either satisfied or not satisfied. This is determined by the "valid" special symbol. The symbol starts out as zero, indicating that the requirement is not satisfied. At any point during the script, you can set the symbol to non-zero, thereby indicating that the requirement is satisfied. The only value that matters is the final value when the script ends, where a non-zero value indicates the pre-requisite is satisfied.

Each pre-requisite is associated with a particular thing. If a pre-requisite is defined for a component, then it is inherited by the things which derive from that component. The pre-requisites are checked for every thing when it is presented as an option for the user to add via a table or chooser. If one or more pre-requisites are not satisfied, the thing is designated as invalid and the failed requirements are shown in the description information for the thing. If the thing is added by the user in spite of the failed pre-requisites, then all the pre-requisites are applied to the pick at the end of every evaluation cycle.

When invoked, a Validate script starts with the container as its initial context. If the object is a pick, the container is the one the pick resides within. If the object is a thing, the container is the prospective container to which the thing will potentially be added. The reason for the container as the initial context is that the pre-requisite test is defined on the thing. Consequently, the thing will know about itself and will typically be looking to verify that the prospective container satisfies the needs of the thing.

For those situations where you also need to access characteristics of the pick or thing, the Validate script provides an alternate context. This context will always be the pick or thing, as appropriate. You can use the "ispick" special symbol to determine whether the pre-requisite is being applied to a pick or a thing.

NOTE! The use of pre-requisites with a Validate script is generally only needed in more complex situations. The "pickreq" and "exprreq" mechanisms are much simpler to use and maintain, and they should cover 90% of the situations where you need to establish a pre-requisite.

Example

A simple pre-requisite might establish a dependency on an attribute value being at least equal to some number. The example below shows a Validate script that tests whether the container has a child pick (strength) that has a final value of at least 13.

if (child[attrStr].field[trtFinal].value >= 13) then
  @valid = 1
  endif