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Even though SIL works just fine as a standalone scripting language outside Jira (for example our installers use SIL to copy the apps to your Jira directory), but inside Jira it it really makes a difference inside Jira.
Architecture
The SIL language is actually independent from Jira. It can be used for any purpose, for instance to be applied for Confluence. It can be applied for anything. On top of the basic interpreter we've also added a Jira specific interpreter that predefines the standard variables, the key variable for instance that represents the key of the issue.
As you can see, Jira SIL interpreter basically extends the capabilities of the standard interpreter. The standard SIL Interpreter provides a registry for all routines and the Issue SIL Interpreter adds the additional routines into this registry including Jira interactions.
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